2

Chapter -1

General Introduction

1.1 History of Ceramic and Ceramic Tiles:

The basic meaning of Greek word ceramic is given in Sanskrit language. In

Sanskrit ceramic means to fire or heat. In Greek language ceramic means

god Ceramos. The ceramic means the art of the potter. This technique is very

ancient but now it become modern. In common word the ceramic means the

combination of clay with other substance in different mixture ratio and then

fired it for hardness. Ceramic are made by following mainly four steps.

(1) Mixing (2) Shaping (3) Drying (4) Firing

At the present time, the term generally denotes all articles developed by heat

in which clays have been used. The German and French. equivalents of

this term are keramic and ceramiake respectively. In the U.S.A. the cement,

lime, glass and enameled iron industries are included in the term ceramic. But

in Europe this is considered undesirable. The art of pot making is the oldest of

all human arts. It is naturally very difficult to trace the development of this art

systematically. In the following paragraphs attempt has been made to give

only a brief history of the development of various types of ceramic industry in

Asia and Europe. Perhaps the first people that used clay articles for their use,

where the ancient Egyptian vessel of terracotta, which were intended to contain

provisions for the deceased have been found in the tombs of the Memphite

period (5000-3000 BC) and some, bricks found under the valley of the Nile are

supposed to have been made about ten thousand years ago. At latter period

these people also discovered the art of making glazed clay-wares, the

remnants of which are still to be seen in their pyramids and temples. The fine

pottery of latter period is most often covered with a thin glaze, colored with sky

blue or pale green sometimes the clay paste itself is colored but more often left

white.

In India, clay products in various forms have been used since very ancient

times’ recent excavations have shown that this art of potting thrived in a fairly

advanced state as early as four thousand years ago. There can be no doubt

that objects found in the excavations of Harappa and Mohenjodaro on the Indus

3

valley are closely connected and roughly contemporary with the Sumerian

antiquities dating from the third or fourth millennium before Christ. These

ceramic-wares have similarity with those of kish and a seal identical with those

found at Harappa and Mohenjodaro has been discovered in the debris beneath

the temple of Hammurabi’s time.

Mention of pottery is made in the Vedic Hymns (2000-3000 BC) but the law of

Manu Condi fined between 6th and 9th Centuries BC are more explicit. Earthen

vessels are universally used in India are potters constitutes one of the great

function castes of the Hindu social system. Much of the prehistoric potteries of

India are of red, brown, and a black tint has shining unglazed surface and is far

superior in design and workmanship to the common forms of today.

Specimens of glaze tiles after the Persian style were unearthed during the

excavations of Gour, a seat of Mahomedan Kings of Bengal during the 11th

century. historically, man has desired to create living spaces which were

beautiful, durable, and user friendly.with that in mind, ceramic tile has been

made by man for 4000 years.beautiful tiles surfaces have been found in the

oldest pyramids, the ruins of babylon, and ancient ruins of greek

cities.decorative tile work was invented in the near east, where it has enjoyed

a longer popularity and assumed a greater variety of design than any where in

the world. during the islamic period, all methods of tiles decoration were

brought to perfection in persia. in europe decorated tiles did not come into

general use outside moorish spain until the second half of the12th century.

the tiles mosaics of spain and portugal,the maiolica floor tiles of rennaisance

italy,the faiences of antwerp, the development of tiles iconography in England

and in the Netherlands, and the ceramic tiles of Germany are all prominent

landmarks in the history of ceramic tile.

In Punjab, the manufactures of glazed tiles or pottery dates from the period of

Chengiz-Khan (1206-1221). The charms of this pottery are the simplicity in

shapes, the directness and property of Ornamentation and the beauty of

coloring.

Porter defined global competitiveness as the National level, as the ability

to export many goods produced with high productivity, which allows the nation

to import many goods involving lower productivity.

4

(Wall tile 518 B.C.Iran ) (Maiolica tile of 16th century Italy)

There are many things and articles are produced by ceramic material .Due to

very important property like hardness, strength, high melting point, electric

conductivity, brittleness, ceramic used to produces many extra ordinary useful

products.

There are so many products producing in ceramic industries the

products are classified as raw materials and manufacturing techniques.

1.2 Origin of the problem :

The basic requirement of human being is Roti, Kapada and Makan.

Now a day ceramic tiles and ceramic ware are become basic requirement of

people in the world. The people demand various types of high qualities ceramic

tiles and other ceramic products are ever increasing. Also high demand of

ceramic tiles and sanitary product in estate market in the world is increasing

day by day. Ceramic tiles and other ceramic material are useful in Industries,

scientific research, medical science, electronics components, space science,

space yaan technology etc. Now a days ceramics materials useful in advance

applications and demand of ceramics materials are increase in feature.

Morbi, Wankaner and Than are Western part of India situated in Rajkot

District Gujarat. More than 400 units are manufacturing ceramic tiles and

ceramic materials and other ceramic building materials of various qualities. Also

20 huge plants of ceramic tiles producing vitrify tiles. Now a day large demand

of vitrify tiles in building construction. The above units producing large

5

quantities of ceramic tiles and other products per day here. Per day turnover in

Rs. 500 crore, so it’s big output oriented industries. The raw materials used to

manufacturing ceramic tiles are mainly from Gujarat, Rajasthan and

Andhrapradesh mine and some material collect from other part of country and

imported from Russia the following raw materials are used to produce ceramic

tiles. (1) Quartz (2) Feldspar (3) Zircon (4) Al2O3 (5) STPP (6) China

clay (7) Bikaner clay (8) opaque glass (9) Transparent glass (10) grog.

(11) Talc (12) volsonite (13) Dolomite (14) Lime stone Etc..

There are many industries in Gujarat developed and manufacturing

glazed tiles, wall tiles, crockery, the development is due to availability of raw

material, availability of natural gas, entrepreneurship of people, well trained

workers and positive policy of State Government. Ceramic industries are in

region of Than, Morbi, Wankaner, Himatnagar, Mahesana and Ahmedabad in

Gujarat.

Now a day technology is developed well but most of ceramic industries

used old technology and producing low quality products and they not able to

provide variety in products many industries suffering from following technical

problems.

1. Standard raw materials can not easily available in ceramic zone.

2. Huge quantities of rejection product during firing process in ceramic

ware.

3. Difficult to stand in market against china products.

4. Fuel cost is very high.

5. High bank interest against bank loan for industries.

6. Old technique in quality control.

7. Old material analytical technique.

8. There is no particular R&D section in major’s plants.

9. Poor mentality to implement high education thought in improvement of

work in ceramic industries.

10. Majority workers are in ceramic industries from out state.

11. Due to impurity present in raw material during the firing huge quantities

of reject product to destroy this waste is a big question It is harmful for

environment.

12. Ignorance of technical knowledge.

6

Due to this reason it is difficult to stand in international competition.

By studying above factor I have decided to study basic raw material of ceramic

tiles, for thermoluminescence. Because T.L.(Thermoluminescence) is very

sensitive to any imperfection in impurity. That’s why TL is very useful tools in

Quality Control in Ceramic tiles raw materials.

The present minerals under study were collected from Bhor ghats,

Sangamaner, Nashik also from various ceramic processing industries Morbi.

Rajkot district in Gujarat.

Over all eighteen verities of the minerals were collected among them the

following nine minerals are selected to TL study ,X RD and TGA. (1)Quartz (2)

Feldspar (3) Zircon (4) Al2O3 (5) Sodium Tri Poly Phosphate (STPP) (6)

7

China clay (7) Bikaner clay (8) opaque glass (Frit-O) (9) Transparent glass

(Frit-T). Two samples namely Grog and Mixture are the part of the pre final and

final product of ceramic tiles these two sample are also subjected to TL

measurement before and after irradiation, XRD study and Thermo Gravimetric

Analysis (TGA). Induction coupled plasma atomic emission spectroscopy

(ICPAES) of three sample namely China Clay, Bikaner Clay and Mixture has

been done.

In ceramic tiles and sanitary ware the manufacturing process is mixing of

various type of minerals in appropriate quantities are taken and ball milled for

six to eight hours in distilled water the obtained slurry is sieved to get

appropriate particle size around 15 micron are collected for further processes.

The present TL study of minerals is intended to suggest the quality of

the raw material at input stage of the ceramic tiles industry. TL dosimetry

studies are done in case any accident like nuclear fall out these ceramic tiles

fixed in the toilet, bathroom, and flooring, may be used to get total radiation

received from the accident day to sample analyzed day.

Ceramic products made from inorganic substance First body of the

ceramic made from clay, quartz and Feldspar as main component and talk,

volosonite, dolomite and also used for making body then give appropriate

shape to the body and fired by suitable temperature, there are so many

conventional ceramic product but mainly are given below :

(1) Virtues sanitary ware: It is high qualities ceramic product made

from clay, Quartz and Feldspar. It has very high hardness.

(2) Dust Press Ceramic Tiles: This tiles is water absorption tiles

mainly made from China clay, Bikaner clay, Volsonite ,Calsite,

Talc.

Stoneware crockery ware: The body of this type ceramic is very hard like stone.

Cup and saucers are made from this type ceramic. Main component made for

plastic clay, china clay, quartz and feldspar. This ceramic fired at temperature

12000C.70% of ceramic product in India provided by Morbi and other unit are in

Rajkot district.

8

Map indicating Sangamner, Nashik ,Maharashtra State, India

1.3 Rocks and Minerals

The earth can be physically described as a ball of rock (the crust or

lithosphere), partly covered by water (the hydrosphere) and wrapped in an

envelop of air (the atmosphere). To these three physical zones one may add

the biological zone (the biosphere). The crust or lithosphere is made up of a

great variety of rocks containing only a handful of elements.

Rocks are the aggregate of minerals and are the individuals units

constituting the crust of the earth or the lithosphere. Some of them were

formed during consolidation of molten silicates (magma) and are describing

as the igneous rocks (granite, basalt etc.). During later periods, the primary

rocks suffered erosion by wind, water, ice, etc. and the products of such

decay were carried away by the natural forces and deposited as loose

sediments. Later on, they were subjected to compaction and the resulting

products are known as the sedimentary rocks (e.g. sandstones and shales).

The rocks occurring in any region may suffer physico-chemical change and

accordingly, develop remarkable changes in their mineral compositions or

texture or both. The processes which bring about such changes are known as

metamorphism and the resulting products are the metamorphic rocks. The

dominant rocks occurring in the crust fall in the two contrasted groups:

9

(a) Light rocks, including granite and related types and sediments such as

sandstones and shales They are rich in silica (65-70%), while alumina is the

most abundant of the remaining constituents.

(b) Dark and heavy rocks, mainly basalt and the related types They are

known as basic rocks (with about 60% silica). Certain heavier rocks called

ultra basic rocks (sp. gr. 3.4, 40-45% silica) are also present. In these rocks,

silica is still the most abundant single constituent but iron oxide and

magnesia, singly or together generally take the second place.

Some of the elements, e.g. gold, copper, sulphur, carbon (as diamond

or graphite) make minerals by themselves but most minerals are compounds

of two or more elements. More precisely, minerals are the natural inorganic

substances of fixed chemical composition and are very commonly

characterized by the presence of typical atomic structure with or without the

development of the corresponding external crystalline form e.g., Quartz. The

study of minerals involves knowledge of their crystalline form, internal

structure, the physical and chemical properties, the optical characteristics and

their mode of occurrence. A mineral from which one or more metals or

metallic compounds can be extracted economically, is known as an ore

mineral, e.g. the mineral bauxite which is an important ore of aluminum metal

as well as aluminum oxide which is an essentional ingredient of certain types

of refractories as well as technical ceramic items.

The Abundance of Elements on the earth’s crust.

Atomic Number Name Volume %

8 Oxygen 91.97

11 Sodium 1.60

12 Magnesium 0.56

13 Aluminum 0.77

14 Silicon 0.80

19 Potassium 2.14

20 Calcium 1.48

26 Iron 0.68

10

Average Composition of Crust Rocks (as Oxide)

Name Chemical Formula %

Silica SiO2 59.26

Alumina Al2O3 15.35

Lime CaO 5.08

Soda Na2O 3.81

Ferrous Oxide FeO 3.74

Magnesia MgO 3.46

Ferric Oxide Fe2O3 3.14

Potash K2O 3.12

Water H2O 1.26

Titania TiO2 0.76

Phos. Pentoxide P2O5 0.28

1.4 Quartz:

Quartz: The purest natural crystalline form of silica is quartz, containing more

than 99.95% SiO2. The other abundant sources of silica are the acid igneous

rocks, sands, sandstones and quartzite containing varying amounts of

impurities. In all these raw materials SiO2 exists in the form of ∝-quartz. Flint,

which is a mixture of chalcedony and quartz, is also used as a source of silica

in some countries.

Under optical microscope, quartz is identified by its colorless,

nonpleochroic habit in plane polarized light; shape is commonly anhedral,

often found as perfect euhedral crystal. It does not show any cleavage, but

some conchoidal fractures are observed within the grains. Anisotropic under

cross polarized light, quartz shows first order interference color which is highly

variable (grey, yellow etc.). It gives adulatory or patchy extinction which is one

of the most characteristic features of Quartz especially in metamorphic rocks.

Refractive index is low, slightly higher than Canada balsam (1.55), the outline

being feebly visible in plane polarized light. Quartz grains often show

numerous tiny vitreous inclusions of other minerals. Quartz is distinguished

from alkali Feldspar by its positive relief in balsam, lack of alteration and

11

cleavage. Quartz lacks the multiple twinning of most Feldspar and differs from

the untwined oligoclase by uniaxial figure and lack of cleavage.

Silica can exist in polymorphic forms. The sequence of polymorphic inversions

can be represented as follows:

α- Quartz (8700C) ↔ α- tridymite(14700C) ↔ α-cristobelite(17260C) ↔melt

↕ ↕ ↕ 5730c 1630c 2000c

β-Quartz β- tridymite β- cristobelite

↕

1170c γ -tridymite The inversions indicated by the horizontal arrows are reconstructive

transformations (relatively slow), during which the bonds in the secondary co-

ordination sphere are broken and the SiO4 tetrahedral are completely

rearranged. The activation energy for the changes is high and as a result the

high temperature forms can be under cooled without transformation to the

stable state. The inversions indicated by the vertical arrows are known as the

displacive type of transformations which proceeds at a relatively fast rate.

In presence of impurities in the form of solid solutions, at about 8700C

∝-tridymite. which gradually transforms to α-cristobalite above 14700C.

Cristobalite ultimately melts at 17260C and on cooling forms vitreous silica.

The quartz-cristobalite transformation starts on the surface or the boundary

face of quartz grains leading at first to formation of a strongly disordered

quartz followed by the formation of a disordered cristobalite. Subsequently it

turns into a regular form. The most important consequence of the polymorphic

transformation of quartz is the changes in the specific gravity and volume

Uses : Quartz is widely used in the manufacture of soda-lime-silica glass

and white wares. Quartzite containing about 98% SiO2 are used for the

manufacture of silica bricks, used in steel making furnaces, specially at the

roof of an acid open-hearth, checkers, converter etc. They are also used in

12

coke-ovens and the roof of glass tank furnace. For refractory use, the

combined Al2O3 and TiO2 should be < 2.5% and for superior qualities < 1%.

With Na2O and K2O < 0.1% CaO < 0.3% and MgO < 0.1%, quartzite are

considered to be of suitable quality.

The pure, untwined, clear and transparent quartz crystals possess

piezo-electric properties and are used in telecommunication. Quartz is also

the source of element silicon, used in the manufacture of non-oxide ceramics

(e.g. SiC, Si3N4) and ferro-silicon.

Chemical Composition of Quartz:

Source Constituents (%)

Quartz SiO2 Al2O3 Fe2O3 TiO2 CaO MgO K2O Na2O LOI

Nizamabad, A.P. 99.75 0.15 0.02 - - - - - -

Hyderabad, A.P. 99.96 - 0.02 - - - - - -

Gujarat 99.40 0.06 0.04 - 0.09 tr. - - .22

Tura, Meghalaya 99.12 0.21 0.36 0.01 - - - - -

Jaipur, Rajasthan 98.11 0.41 0.22 tr 0.68 tr. 0.07 0.15 .19

Hyderabad

(Sanatnagar)

99.13 0.12 0.13 0.07 0.09 tr. 0.10 0.06 .19

1.5 Feldspar :

Feldspar is the most important group of rocks forming silicate

(tectosilicate) minerals. The acid intrusive rocks (pegmatite) are the chief

source of Feldspars.

At high temperatures there is a continuous series of solid solution

between potash-Feldspar and soda-Feldspar. These types of Feldspar are

mainly found in alkali igneous rocks like granite, syenites etc. and also in

some metamorphic rocks. Large quantities of Feldspars suitable for ceramic

industry are found in Rajasthan and also in Tamilnadu, Gujarat, Orissa, Bihar,

M.P. and in West Bengal.

Uses : Feldspar is a common flux and is used in various types of ceramic

bodies, the fluxing action depending on the amount and type of alkalies

present. Unlike pegmatites and nepheline syenites, feldspar has a rather slow

13

fluxing action due to the high viscosity of the melt. Potash feldspar is generally

preferred in ceramic glazes. Potash spar fuses at cone 8 to 9 as compared to

cone 4 for some high soda spars. In a fired body it increases the strength,

hardness and coefficient of expansion and improves the transluscency and

vitrification.

Feldspars are also used in glazes, enamels and glass as a cheap

source of alkalies. For use in glass, the ferric oxide content should be less

than 0.2%, silica not more than 67% and alumina not less than 17%. Potash

spars are more commonly used in glass since pure varieties are more

abundantly available.

Occurrence and chemical composition of Feldspar

Source Constituents (%)

Feldspar SiO2 Al2O3 Fe2O3 TiO2 CaO MgO K2O Na2O LOI

Mihijam,

Jharkhand

65.90 19.34 0.29 0.04 0.35 tr. 9.27 8.07 0.04

Kodarma,

Jharkhand

64.00 18.83 0.39 - 0.55 - 12.02 3.11 0.21

Alwar (1)

Rajasthan

65.56 20.93 0.12 - 2.05 tr. 7.12 3.49 0.42

Alwar (2)

Rajasthan

64.96 19.62 0.11 - 1.02 0.02 12.38 1.98 0.64

Jhansi, M.P. 63.69 21.88 0.24 - 0.34 tr. 11.25 2.72 0.86

Nellore,

A.P.

64.80 19.09 0.20 - 0.18 0.01 13.00 2.40 0.5

Sitampudi,

Tamilnadu

44.84 34.07 0.05 - 20.0

5

0.50 - - -

Raghudih,

W.B.

64.70 19.54 0.36 - - - 11.42 2.46 -

Chandla,

M.P.

66.25 10.21 0.29 - - 0.40 13.81 - 0.50

Ajmer,

Rajasthan

65.17 21.07 0.13 - - - 12.80 0.78 0.05

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1.6 Clays and related minerals :

Clays are essentially hydrated aluminosilicate minerals having fine

particle sizes, usually below 2 microns. Clay minerals have layered structures

and occasionally aluminum is replaced by magnesium, iron, alkali or alkaline

earth elements partly or wholly.

The important physico-chemical properties of clays depend not only on

the composition and structure of the respective clay minerals, but also on the

particle size and shape. The principal clay minerals are as follows :

Kaolinite Group: Kaolinite (Al2O3, 2SiO2, 2H2O) is normally well crystallized as

hexagonal plates (0.1-0.3µ), has a medium plasticity and base exchange

capacity.

Halloysite (Al2O3, 2SiO2, 4H2O): It has a two layer structure containing

weakly bound molecules of water between the structural layers, which is given

out even at 400 C. The particles are of elongated shape (rods and tubes). The

mineral has a higher exchange capacity and plasticity due to finer particle size

in comparison to kaolinite. It is frequently associated with kaolin and kaolinitic

clay.

Montmorillonite Group : Montmorillonite Commonly exists as fine

particles having sizes less than 1µ. It has a three-layered structure consisting

of two layers of silica tetrahedral and one central di-octahedral or tri-

octahedral layer. The gaps between the layers are readily penetrated by water

which produces swelling. The mineral exhibits high degree of dispersion,

plasticity, swelling property and base exchange capacity. It shows high drying

and firing shrinkage.

Bentonite is a montmorillonitic clay, having properties similar to that of

montmorillonite.

Formation of Clays:

Clays are said to have originated from weathered igneous rocks

composed of Feldspar and Quartz. The reactions during weathering of

Feldspar leading to formation of clay a given below. The steps involved are

essentially (a) hydrolysis (b) decomposition and (c) hydration.

(a) K2Al2Si6O16 + 2H2O → H2 Al2Si6O16 + 2KOH (removed by water flow)

(b) H2Al2Si6O16 → H2 Al2Si2O8 + 4SiO2

15

(c) H2Al2Si2O8 + H2O →Al2 (Si2O5) (OH)4

When the environment provides carbonic acid.

(d) K2Al2Si6O16 + 2H2CO3 Al2 (Si2O5)(OH)4 + K2CO3 + 4SiO2

Here also K2CO3 is leached out by rain water. When the parent rock

contains impurities like lime, magnesia, iron etc. impure clays are obtained.

Simulated laboratory experiments reveal that kaolinite is the end product

under acidic conditions whereas the presence of alkalies (potassium in limited

concentration) favors formation of smectite or mica. Under similar conditions,

if magnesium is present, montmorillonite is formed. At or above 3500C and

under a moderate pressure, pyrophyllite is formed in presence of an excess

Al2O3, from boehmite. At higher temperatures other Al2O3 phases develop.

Types of Clays:

Kaolin primarily consists of kaolinite mineral. Two types of kaolin are

recognized namely, (a) Residual or primary kaolin and (b) Sedimentary or

secondary kaolin which are finer in size.

Bikaner Clay is a highly plastic kaolinitic clay, having very fine particle

size. It has a softening point (16750C) lower than that of pure kaolin and is

sometimes used as bonding clay in refractories. The main use is in white ware

compositions to improve the plasticity, workability and the green strength of

the finished products.

Fireclays have a disordered kaolinitic structure and unlike pure kaolin,

are not white burning, primarily due to the presence of iron oxide and titania

as impurity in the clays. Fireclays can be classified under the following

categories as follows:

(i) Flint clay-A dense, hard, non-slakable, massive, non-plastic clay

having flint like nature. These are composed of fine, well-

crystallized kaolinite particles.

(ii) Plastic clay-soft and plastic

(iii) Refractory shales – soft and highly plastic.

Fire clays occur in two modes namely:

(a) Well defined beds associated with coal seams.

(b) Lenticular beds associated with coarse sediments.

16

The color and other characteristics of fireclay depend on the mode of

formation.

Clays generally contain appreciable amounts of Organic matter, such

as lignite or humic acid. The mineral impurities commonly present are quartz,

feldspars, micas, iron and titanium bearing minerals, limestone, magnesite,

gypsum, garnet and tourmaline. Excepting quartz, the other impurities act as

fluxes and reduce the Pyrometric Cone Equivalent (PCE).

Chemical Composition of Some Indian Clays:

Source Constituents (%)

SiO2 Al2O3 Fe2O3 TiO2 CaO Mg

O

K2O Na2

O

LOI

West Zone

Gujarat

Kutch Mineral 47.75 34.25 0.90 1.30 1.23 0.24 0.35 0.45 12.46

Premier Minerals 44.17 36.55 0.70 2.82 1.12 0.12 0.10 0.42 13.92

Ashapura 49.63 34.05 0.60 1.37 0.54 0.58 0.22 0.61 12.28

Amrapali I 43.08 36.59 1.16 2.31 1.79 0.85 1.07 0.22 13.00

II 46.21 35.08 0.87 1.29 0.88 0.86 0.20 0.48 13.88

III 44.64 34.94 1.34 1.14 1.67 0.91 0.16 0.10 14.84

Eklera 48.92 22.59 1.30 1.12 0.65 0.28 1.00 0.31 12.83

Nadapar IRL 43.86 38.24 0.50 1.74 0.67 0.24 0.05 0.55 14.05

Nadapar ISWL 44.04 39.25 0.40 0.96 0.45 0.16 0.05 0.52 14.09

Umiya 47.20 36.15 0.60 1.50 0.82 0.04 0.05 0.33 13.59

AMI China clay 52.45 29.83 0.94 1.48 1.14 0.59 0.35 0.86 11.89

Himmar Nagar

China clay 45.90 37.74 0.57 0.69 0.76 0.18 0.12 - 14.13

East Zone

Bihar

Rajmahal (Pink) 46.68 35.29 1.90 0.89 0.28 0.50 0.28 0.60 13.12

Rajmahal (White) 48.90 34.51 1.71 0.50 0.67 0.20 0.41 0.52 12.60

Chaibasa (Gr. I) 47.90 36.00 1.25 tr. 1.24 0.40 0.61 0.75 12.25

Chaibasa 46.59 35.95 1.12 tr. 1.40 0.40 0.33 0.91 13.22

17

Source Constituents (%)

(Superfine)

Simultala 47.27 38.20 0.47 0.07 0.35 0.10 1.55 0.14 11.80

Ulatu 44.35 38.51 0.55 1.23 0.23 0.05 0.05 0.11 14.77

Bagru 45.09 37.45 1.12 2.40 tr. tr. 0.10 0.13 13.57

West Benal

Mukhdum Nagar I 44.10 37.39 2.6 1.37 0.10 tr. 0.20 0.79 13.48

II 43.64 35.58 2.39 2.64 1.80 tr. 0.13 0.36 13.50

Mhatomara 46.05 35.49 1.36 2.11 0.28 0.20 0.27 0.03 13.86

Mahammad Bazar 44.31 36.97 2.11 0.80 0.31 0.26 0.60 0.29 14.34

Kharidumri 46.98 36.87 0.54 0.40 0.78 0.11 0.42 0.13 12.98

Dhatara 47.45 33.62 1.13 tr. 1.87 1.25 0.52 1.08 13.17

Orrisa

Mayurbhanj 48.55 33.69 1.45 0.53 tr. 1.27 - 0.17 11.16

North Zone

Kusumpur 46.80 36.83 1.65 tr. 0.03 0.07 0.57 0.11 13.63

Delhi I 46.92 36.04 1.86 tr. 0.92 0.26 1.06 0.39 12.76

II 47.66 35.75 1.00 tr. 1.01 0.20 0.99 0.53 12.86

Rajasthan

Modi Clay (P-90) 44.46 37.03 0.80 tr. 2.00 0.41 0.07 1.02 14.64

Modi Clay(TT-75) 46.82 36.72 1.00 0.21 0.70 0.25 0.15 0.18 13.87

South Zone

Kerala

Thiruvanantapurm 45.60 37.40 0.745 0.89

9

tr. 0.414 0.02

0

0.02

2

14.86

Sasthavattom 44.11 38.17 1.30 1.55 tr. 0.042 0.02

4

0.43

9

14.26

Kannanalloor,

Quilon

43.99 39.64 0.40 0.48 tr. 0.336 0.00

9

0.03

4

15.26

Nyleswar

(Jyothi),Cannanore

45.85 36.74 1.82 1.17 0.08 0.12 0.08 0.13 14.29

Nyleswar (Neelex)” 45.88 36.12 1.43 0.55 0.11 0.21 0.09 0.06 14.94

18

Source Constituents (%)

Nyleswar(Kerala) “ 47.32 35.97 1.30 1.07 0.26 0.22 0.04 0.07 14.09

Nyleswar,

Cannanore

47.94 36.43 1.30 0.93 tr. 0.12 0.20 - 13.35

Payyangadi,

Cannanore

44.87 36.94 1.28 0.94 tr. 0.31 0.23 0.09 15.43

Kannapuram “ 42.72 38.95 3.89 0.48 0.05 0.27 0.19 0.13 13.19

Mulavana, Quilon 47.85 36.70 0.71 0.33 tr. 0.44 0.13 0.11 14.04

Kalluvathukkal 47.91 35.26 1.64 0.40 0.23 0.35 0.23 0.23 13.67

Thiruvanantapurm 46.47 38.13 0.28 0.79 tr. 0.59 0.02 0.08 14.20

Thonnakkal, “ 46.44 37.85 0.33 0.69 tr. tr. 0.08 0.12 13.88

Thonnakkal Grey “ 45.91 37.21 0.90 0.67 tr. 0.27 0.46 0.19 14.37

Thonnakkal Red “ 45.86 34.53 3.05 0.95 0.11 0.36 0.56 0.27 13.82

Pallipuram White “ 46.48 33.21 2.49 0.99 0.23 0.65 0.80 0.15 15.02

Ramapuram,

Cannanore

42.97 36.19 3.73 1.90 tr. 0.74 0.29 0.58 13.73

Payyangadi, “ 41.75 33.37 5.02 2.16 tr. 0.89 0.30 0.48 15.99

China Clay:

The best quality china clays are found in Kundara, Quilon and also in

Cannanore, Ernakulam, and Trivandrum districts of Kerala. The estimated

total reserve of crude clay is 7.5 lakh tones. The spray dried Kaolin is

marketed under the trade name “Kundara Kaolex”. Processed clays from

Kannapuram, Payyangadi and Nylswar (Cannanore) do not conform to the

Grade-I due to high Fe2O3 and TiO2 which can be removed by High Intensity

Magnetic Separation (HIMS). Grade I china clays are available at

Marthandamkonam and Thonnakkai (Trivandrum). The total estimated

reserves in the area is nearly 222 lakh tones.

Good quality China clays occur near Gollahalli, (South Kanara), near

Karalgi in the Khanpur taluk, Belgaum.

The Bageshpura deposit in Hassan is being used in ceramic industry.

In Gujarat (West Zone), china clays available do not conform to Grade I

19

although some of them can be upgraded by HIMS. In the East Zone good

quality clays are available in Simultala (Bihar) and Kharidumri (West Bengal).

Impurities present in other clays limit their use in white ware manufacture. In

Rajasthan, some of the Nim-ka-Thana china clays conform to the

specifications for the Grade I but they are not suitable for casting slips due to

high CaO contents. Also in Rajasthan near Badana and Khanda Sirol (Kota)

good quality china clay is said to occur. A new deposit has been discovered

near Karabaria-ka-Ganta, about 7 kms to the southeast of Udaipur. The

estimated reserves are nearly 398 lakh tones, in addition to about 339 lakh

tones of brown and buff coloured clays. A number of deposits have also been

discovered in other states and explorations are in progress.

Ball/Plastic Clays:. Ball clays conforming to the Grade I plastic clays are

almost non-existent. However, many of them are widely used in whiteware.

These are from Bhimadole and Ellore in Andhra Pradesh. Than in Gujarat.

Kumbalam, Paddappakara, Ramapuram and Payangadi in Kerala, Chandia in

M.P. Bikaner in Rajasthan. Panruti and Neyveli in Tamilnadu and Rajhara in

Bihar. Of these, Bikaner and Than are considered to be best. For H.T.

insulators plastic clays are imported. However, Than and Neyveli clays are

used in small amounts after purification.

Clays are widely used in the manufacture of ceramics such as earthenware,

fine china, stonewares, bricks, tiles, pipes aggregates in castable, mortars etc.

The fine grained kaolinites mixed with montmorillonites find application in

foundry moulding sands. Purer forms of kaolin have extensitve applications in

paper, textile, rubber and cosmetic industries. As a decolouriser of oils it is

known as ‘fuller’s earth’. Mixtures of montmorillonites and kaolinites are also

used as cracking catalysts for heavy petroleum fractions. Other areas of

limited use are leather, paint, plastics, soaps, polishing compounds,

emulsifying agents, medicine etc.

Fire Clays: Fire clays are used in the manufacture of a wide range of

aluminosilicate refractories with varying Al2O3 contents ( 24 to 70%). A good

quality of fire clay has 24 to 26 percent water of plasticity and firing shrinkage

in the range 6 to 8 percent. The three processes generally employed for

beneficiation of clays are (a) Size separation through simple levigation

20

technique; (b) Hydrocycloning by a wet route; (c) Magnetic Separation by

High Intensity Magnetic Separator (HIMS); (d) Froth floation and (e) Chemical

treatments, such as, acid leaching and bleaching.

1.7 Zircon :

Zircon (ZrSiO4) is found in nature as an accessory mineral in igneous

rocks such as granite and pegmaties. More commonly, it is found as a

constitutent of beach sand along with ilmenite, monazite etc.

Zircon crystallizes in tetragonal system and the large crystals occur as

square prisms or in irregular forms. Finer crystals occur as grains of sand-

size. Its hardness is 7.5 and the sp.gr. Varies in the range 4.2 to 4.86 at

15400C and above zircon breaks down to zirconia (ZrO2) and silica which on

cooling recombine to form zircon. Optically, zircon sands are colourless,

subrounded to rounded in nature.

Baddeleyite is a relatively uncommon rock mainly composed of

zirconia. Artificial crystals of baddeleyite are prepared from zircon. It occurs as

tabular monoclinic crystals.

Occurrence

Andhra Pradesh: Crystals of zircon occur as a minor constiuent of

nephline syenites in Khammam; coastal areas of Vishakhapatnam and

Bhimunipatnam, as a constituent of monazite-ilmenite sands.

Kurnool: Chandrapalle, Marrikunta, Yaparlapadu and Gadidemdygu,

minor occurrences.

Bihar: Hazaribagh: Domchanch; pegmatite veins producing zircon

crystals. Gaya : Akbari Pahar.

Kerala: Palghat :Chowghat-Blangad, Veliyangad; beach sands

containing 2.7 to 8.7% zircon, Chavara in Quilon.

Tamilnadu: Manavalakurichi, Kanyakumari; beach sands constaining 5

to 6% zircon.

21

India’s estimated reserve of zircon is about 3.6 million tones. The high

purity zircon is produced after several stages of electrical, magnetic and

gravity separations.

Uses: Zircon nozzles of different shapes are used for continuous casting of

steel. Zircon-alumina refractories in different shapes are widely used as

feeder refractories in the glass industry. In ceramics, zircon has manifold

applications, mostly for its very high refractoriness and chemical resistance. It

often forms an important constituent of chemical stoneware and porcelain

bodies. In glaze and enamels, it is used as an opacifier. Due to the high

hardness and abrasion resistance, it is used for making high density grinding

media. Premium grade zircon is used for production of high performance

electrofused refractories and ultra-white grade of tiles, sanitaryware and

tablewares. The major uses of zircon are as follows:

(a) Refractory for Steel and Glass Industry 35%

(b) Ceramics 25%

(c) Foundry 21%

(d) Others 19%

The world supply of zircon has grown from 0.68 m tones in 1979 to

about 1.09 m tones in 1990 and expected to grow further at the rate of about

4% per year. The demand for zircon in foundries and in refractories, non-

ferrous and ceramics industries is increasing at a rate of 2.6% to 3.0% and

5.0% respectively. A new area of demand has opened up for zircon in the field

of zirconia ceramics. It is estimated that the demand of zircon for zirconia

ceramics is around 0.185 m. tones in the world and is expected to grow at an

annual rate of 6.5%used for neutron absorption.

1.8 Bauxite :

The term ‘Bauxite’ does not refer to a specific mineral but to rocks

consisting chiefly of the hydrated aluminium oxides namely gibbsite, boehmite

and diaspore.

Bauxite can be difined as a rock composed of aluminium hydroxide,

besides impurities in the form of silica, clay, salt and iron hydroxide. The

22

mineral content of bauxite bears a close relationship with the residual

ferruginous rock (laterite) commonly found in tropical regions. Bauxite and

laterite show a tendency to occur together and it is not easy to distinguish

them from their chemical compositions. Bauxite usually contains certain

principal ore forming minerals, minor constituent minerals and mineral

impurities. The principal ore forming mineral of bauxite is Gibbsite, along with

Boehmite, Diaspore, and hydrated iron oxides in minor amounts.

Gibbsite is colourless to pale brown in thin section, feebly pleochroic

and commonly occurs as tiny tabular crystals, showing pseudohexagonal

outline. Perfect basal [001] cleavage may be present. The interference

colours are first order grey, white or yellow. Normal twinning is common on

[001] plane, oblique extinction is nearly 250. Coarse platy gibbsite occurs in

circular and lenticular patches and is generally surrounded by medium to fine

grained gibbsite. The occurrence of the scattered flower like growth of coarse

platy gibbsite in places are very common within fine gibbsite grains mixed with

iron oxide. Deep reddish brown iron and titanium oxides are generally

associated in patches with medium to fine grains of gibbsite. In places

gibbsite grains of different sizes are also seen in the red matrix showing

presence of an aluminous core in a ferruginous mantle.

Diaspore is observed under the microscope as blades, radiating from

center and cleavage is perfect to [001]. Elongated crystals give straight

extinction and are usually colourless in plane polarized light. They show first

order interference color of blue, green etc., refractive index is higher than that

of balsam.

Bauxite deposits were formed from all types of alumina bearing rocks.

Such rocks are rich in feldspar, amphiboles, pyroxene and clay minerals. The

rock type includes syenite, granite, basalt etc. It is a product of chemical

weathering of aluminous minerals such as feldspar, nepheline and corundum.

Intensive weathering effects are evident from the redistribution of the

insolubles.

Alumina can exist in various forms. On heating bauxite, it loses the

chemically combined water turning first to gamma alumina and finally to alpha

23

alumina. Conversion to alpha alumina is complete at 1300-14500C. The

common impurities present in bauxite are kaolinitic clay, quartz, calcite,

(calcium carbonate) iron oxide (limonite) and various hydroxide bearing

minerals. The iron oxide content is generally above 2 to 3% and often more

than 5%. Bauxite rock is normally medium soft to hard in nature. It has a

cellular, porous or fine grained compact structure and shows a conchoidal or

uneven fracture pattern. The color ranges from light grey, cream, yellow or

pink to dark brown and dark red, depending on the amount of coloring

impurities, particularly iron oxide present in the mineral.The different grades of

bauxite mostly occur in the states of Andhra Pradesh, Madhya Pradesh,

Chattishgarh, Bihar, Jharkhand, Gujarat, Maharashtra, Tamilnadu and

Jammu & Kashmir.

The chemical composition of some important Bauxites:

Source Constituents (%)

SiO2 Al2O3 Fe2

O3

TiO2 CaO MgO K2O Na2O P2O LOI

Gujarat-I 1.53 55.61 4.32 1.94 3.42 1.23 0.24 0.08 - 28.1

Gujarat-II 4.00 59.27 2.79 1.93 0.45 tr 0.08 0.34 - 3.74

Gujarat-III 2.50 55.23 6.19 3.00 2.90 ND ND ND - 30.00

Saurashtra,

Gujarat

1.40 60.75 1.85 0.30 - - - - 0.01 32.30

Ratnagiri,

Maharashtra

3.00 49.2 14.2 4.0 - - - - - 28.10

Belgaun,

Karnataka

3.00 59.00 3.55 8.02 - - - - - 28.10

Katni, M.P. 6.70 55.10 4.52 7.78 - - - - - 26.81

Kolaba 1.28 59.20 4.90 4.15 0.25 0.18 - - 0.08 29.62

24

Uses: Bauxite is larely consumed by aluminium industry where ferruginous

bauxites with a low silica content and having an alumina to silica ratio>3 are

preferred. Bauxite is used in high alumina refractory compositions. It melts

between 1740-18200C. In refractory grade bauxites total magnesia, lime,

potash and soda content should not exceed 1%. Those containing higher

amounts of silica (sialites) can be used provided the iron content is low.

Bauxite and diaspore based refractories contain more alumina than those

containing sillimanite group of minerals but higher amounts of glassy phase,

lack of volume stability and porosity restrict the use of bauxite as refractory

raw material. It is also used for the manufacture of special ceramic items such

as abrasion resistant dies for wire drawing and chemically resistant ceramics.

1.9 Frit :

Frit is a ceramic composition that has been fused, quenched to form a glass,

and granulated. Frits form an important part of the batches used in

compounding enamels and ceramic glazes; the purpose of this pre-fusion is to

render any soluble and/or toxic components insoluble by causing them to

combine with silica and other added oxides.

In antiquity, frit could be crushed to make pigments or shaped to create

objects. It may also have served as an intermediate material in the

manufacture of raw glass. The definition of frit tends to be variable and has

proved a thorny issue for scholars. In recent centuries, frits have taken on a

number of roles, such as biomaterials and additives to micro wave

dielectric ceramics.

Archaeologists have found evidence of frit in Egypt, Mesopotamia,

Europe, and the Mediterranean. The definition of frit as a sintered, polycrystal

line, unglazed material can be applied to these archaeological contexts. It is

typically colored blue or green.

25

Composition of Some Special Frits for Wall Tiles:

Borosilicate First (Opaque)

Borosilicate Frit (Opaque)

Lead Boro silicate Frit (Opaque)

Lead Boro-silicate Frit (Semi Opaque)

Lead Boro –silicate Frit (Transparent)

Lead Boro silicate Frit (Transparent)

SiO2

Al2O3

Fe2O3

TiO2

CaO

MgO

Na2O

K2O

PbO

BaO

Zno

ZrO2

B2O3

LOl

62.00

8.60

0.30

Tr

3.83

0.69

4.50

2.00

-

-

-

9.14

8.71

0.30

55.40

8.30

0.26

0.05

4.55

2.90

5.00

0.63

-

6.15

-

8.53

8.20

0.24

52.91

6.81

0.18

Tr

5.59

0.46

5.05

0.88

9.80

1.70

-

8.87

7.20

-

35.76

8.75

0.13

Tr

4.95

0.20

3.08

2.25

26.23

3.25

7.24

2.50

15.30

0.45

58.43

7.09

0.33

Tr

4.55

0.10

6.30

1.45

12.03

1.83

-

-

7.26

0.36

42.23

4.86

0.02

Tr

4.40

0.10

4.58

0.66

27.51

0.58

6.13

-

8.67

0.26

Uses of Frit: Frits are indispensable constituents of most industrial ceramic

glazes which mature at temperatures below 1150°C. Frits are typically

intermediates in the production of raw glass, as opposed to pigments and

shaped objects.But they can be used as their own entities in a number of

high-tech contexts. Frits made predominantly of silica, diboron trioxide, and

soda are used as enamels on steel pipes.Another type of frit can be used as a

biomaterial. Molten soda-lime-silica glass can be “poured into water to obtain

a frit,” which is then ground to a powder. These powders can be used as

“scaffolds for bone substitutions.” Also, frits can be added to high-tech

26

ceramics. Scientists have made such frits by milling ZnO and

H3BO3 with zirconium beads, then heating this mixture to

1100°C, quenching it, and grinding it. This frit is then added to a

Li2TiO3 ceramic powder. This addition is beneficial: the ceramic can sinter at a

lower temperature while still keeping its “microwave dielectric properties."1.10

Sodium Tripolyphosphate :

(STPP, sometimes STP or sodium triphosphate or (STPP), with formula

Na5P3O10, is a polyphosphate of sodium. It is the sodium salt of triphosphoric

acid. sodium tripolyphosphate is prepared by heating a stoichiometric mixture

of disodium phosphate, Na2HPO4 and monosodium phosphate,

NaH2PO4 under carefully controlled conditions.

2Na2HPO4 + NaH2PO4 → Na5P3O10 + 2H2O

Uses: It is used in various applications such as a preservative for seafood,

meats, poultry and pet foods. It is also used in toothpaste and as a builder

in soaps and detergents, improving their cleansing ability. The United

States Food and Drug Administration lists STPP as "generally recognized as

safe", along with salt, vinegar, and baking powder.

STPP is a solid inorganic compound used in a large variety of

household cleaning products, mainly as a builder, but also in, a

human foodstuffs animal feeds, industrial cleaning processes

and ceramics manufacture. STPP is widely used in regular and compact

laundry detergentsand automatic dishwashing detergents (in powder, liquid,

gel and/or tablet form), toilet cleaners, surface cleaners, and coffee urn

cleaners .

Food Applications:

In foods, STPP is used to retain moisture. Many governments regulate

the quantities allowed in foods, as it can substantially increase the sale weight

of seafood in particular.

Many people find STPP to add an unpleasant taste to food, particularly

delicate seafood. The taste tends to be slightly sharp and soapy and is

particularly detectable in mild-tasting foods. The increased water holding

properties can also lead to a more diluted flavor in the food.

27

References

1. Source Book of ceramic Part-1 – S Kumar Agust-2002

2. A study of ceramic India .in Global era by -S.N Ramsariya , research paper 2003

3. Alien M. Alper , High temperature Oxides-part -1 – academic press ,

new York , 1970

4. F.H Nortion, refractories , 3rd Edn.- Megraw Hill Book Co. Inc, 1949

5. Jan – Hlavac The Technology of Glass & Ceramics - An Introduction, Elsevier Scientific Publishing, Co. New York, 1938

6. Kirk – Othmer, Encyclopedia of chemical technology – 3rd Edn Vols

3,12,14,15,19,22,& 24 Wiley – Inter – Science Publication , John, Wilely & sons , New York

7. N.A.. et al. Toropon Phase Diagram of Silicate Systems ( in Russian )

.- Iza Nanka, Leningrad, 1970

8. P.P Budnikon The technology of ceramics & Refractories Translation of Scripta Techniqa, Edward Arnold (publishing) – Ltd London, 1964

9. S.K. Guha, Ceramic raw Materials of India – A Directory , Indian,

Institute of Ceramics, 1928

10. W.D Kngery, Introduction to ceramics , - John Wiley & sons, Inc, New York, 1960

11. D.K Banerjee , Mineral Resources of India, - The World press Pvt. Ltd , Kolkatta, 1992

12. Indian Minerals Hand Book,- Indian Bureau of Mines , 1998 &1999 13. Nina – Keegan – Industrial Mineral Directory ,- 4th Edition, Industrial

minerals information Ltd, U.K. 1999

14. A.V Sankaran, K.S.V Nambi & C.M Sunta – progress of Thermonluminescence reasearch on Geological Materials – 7th September, 1982

15. Amin , Y.M Bull R.K. & Durrani, S.A. (1982) Effect of radiation

damage on T.L properties of crystals, Third specialities Meeting on T.L & ESR dating, Helslinger Counc, Eur, PACt J,9

16. J.P Patel G.H . Upadhaya – Material Science , Atul Parakashan,

2006-07 17. Material Science – S.L Kakani – New Age Int. Pub. 2006

28

18. Saxena Gupta – Solid State Physics – 1985 19. H.V Keer – Sollid State Physics – Wilay Eastern Ltd. 1993

20. Azaroff – Introduction to Solid ,1977

21. Skoog , Holler, Nieman – Parinciples of Instrumental Analysis, 5th

Edition 2005 22. M.J Aitken – Thermo. Lumi. Dating ,1985

23. P.L Soni . Mohan Katyal – Text Book of Inorganic Chemistry, 2007

24. D . J Mc Dougall – Thermo . Lumi . of Geological Materials,

Academic press , London & New York , 1984

25. Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., Pearse, Roger (2002-09-16). Stwertka, Albert (1996). A Guide to the Elements. Oxford University Press. pp. 117–119..

26. http://www.etymonline.com/index.php?term=zircon

27. Ushikubo, T., Kita, N.T., Cavosie, A.J., Wilde, S.A. Rudnick, R.L. and

Valley, J.W. (2008). "Lithium in Jack Hills zircons: Evidence for extensive weathering of Earth's earliest crust". Earth and Planetary Science Letters 272: 666–676

28. Nemchin, A.A., Pidgeon, R.T., Whitehouse, M.J. (2006). "Re-

evaluation of the origin and evolution of >4.2 Ga zircons from the Jack Hills metasedimentary rocks". Earth and Planetary Science Letters

29. John M. Hanchar & Paul W. O. Hoskin (eds.) (2003). "Zircon".

Reviews in Mineralogy and Geochemistry, 53. ISBN 0-939950-65-0 (Mineralogical Society of America monograph).

30. D. J. Cherniak and E. B. Watson (2000). "Pb diffusion in zircon".

Chemical Geology 172: 5–24.

31. Hermann Köhler (1970). "Die Änderung der Zirkonmorphologie mit dem Differentiationsgrad eines Granits". Neues Jahrbuch Mineralogische Monatshefte 9: 405–420.

32. K. Mezger and E. J. Krogstad (1997). "Interpretation of discordant U-

Pb zircon ages: An evaluation". Journal of Metamorphic Geology 15: 127–140..

33. J. P. Pupin (1980). "Zircon and Granite petrology". Contributions to

Mineralogy and Petrology 73: 207–220.

34. Gunnar Ries (2001). "Zirkon als akzessorisches Mineral". Aufschluss 52: 381–383..

29

35. John W. Valley, William H. Peck, Elizabeth M. King, Simon A. Wilde (2002). "A Cool Early Earth". Geology 30: 351–354. Retrieved 2005-0411.

36. G. Vavra (1994). "Systematics of internal zircon morphology in major

Variscan granitoid types". Contributions to Mineralogy and Petrology

37. Guggenheim, Stephen; Martin, R. T. (1995), "Definition of clay and clay mineral: Journal report of the AIPEA nomenclature and CMS nomenclature committees", Clays and Clay Minerals 43: 255–256,

38. Ehlers, Ernest G. and Blatt, Harvey (1982). 'Petrology, Igneous,

Sedimentary, and Metamorphic' San Francisco: W.H. Freeman and Company. ISBN 0-7167-1279-2.

39. Hillier S. (2003) Clay Mineralogy. pp 139–142 In: Middleton G.V.,

Church M.J., Coniglio M., Hardie L.A. and Longstaffe F.J.(Editors) Encyclopedia of sediments and sedimentary rocks. Kluwer Academic Publishers, Dordrecht.

40. Dictionary of Ceramics (3rd Edition) Edited by Dodd, A. Murfin, D.

Institute of Materials. 1994.

41. T. Pradell et al. 2006, Physical Processes Involved in Production of the Ancient Pigment, Egyptian Blue, Journal of the American Ceramic Society 89.4: 1431.

42. L. Lee and S. Quirke 2000, Painting Materials, In: P.T. Nicholson and I. Shaw (eds.), Ancient Egyptian Materials and Technology, Cambridge: Cambridge University Press, .

43. G.D. Hatton, A.J. Shortland, and M.S. Tite 2008, The Production

Technology of Egyptian Blue and Green Frits from Second Millennium BC Egypt and Mesopotamia, Journal of Archaeological Science 35: 1591.

44. D.A. Stocks 1997, Derivation of Ancient Egyptian Faience Core and

Glaze Materials, Antiquity 71: 181.

45. P. Bianchetti et al. 2000, Production and Characterization of Egyptian Blue and Egyptian Green Frit, Journal of Cultural Heritage 1: 179; Hatton, Shortland, and Tite 2008, 1592.

46. A.L. Oppenheim et al. (eds.) 1970, Glass and Glassmaking in Ancient Mesopotamia, Corning: The Corning Museum of Glass, 22-23, 118.

47. P.T. Nicholson and J. Henderson 2000, Glass, In: P.T. Nicholson and

I. Shaw (eds.), Ancient Egyptian Materials and Technology, Cambridge: Cambridge University Press, 199.

30

48. A.L. Oppenheim 1970, The Cuneiform Texts, In: A.L. Oppenheim et

al. (eds.), Glass and Glassmaking in Ancient Mesopotamia, Corning: The Corning Museum of Glass, 35.

49. R.H. Brill 1970, The Chemical Interpretation of the Texts, In: A.L.

Oppenheim et al. (eds.), Glass and Glassmaking in Ancient Mesopotamia, Corning: The Corning Museum of Glass, 113.

50. A.K. Bernsted 2003, Early Islamic Pottery: Materials and Techniques,

London: Archetype Publications Ltd., 25; R.B. Mason and M.S. Tite 1994, The Beginnings of Islamic Stonepaste Technology, Archaeometry 36.1: 77

51. 'Potter and Ceramics. Rosethal E. Pelican Books. 1949

52. Dictionary of Ceramics (3rd Edition) Edited by Dodd, A. Murfin, D.

Institute of Materials. 1994.

53. Dictionary of Ceramics (3rd Edition) Edited by Dodd, A. Murfin, D. Institute of Materials. 1994.

54. 'Ceramics Glaze Technology. Taylor J.R. & Bull A.C. Pergamon

Press. 1986. 55. Moorey 1985, 134-135.

56. O.R. Lazutkina et al. 2006, Glass Enamel for Steel Based on

Diatomite Material, Glass and Ceramics 63.5-6: 170.

57. C. Vitale-Brovarone et al. 2008, Biocompatible Glass-Ceramic Materials for Bone Substitution, Journal of Materials Science 19: 472.

58. J. Liang and W. Lu (in press) 2009, Microwave Dielectric Properties

of Li2TiO3 Ceramics Doped with ZnO-B2O3 Frit, Journal of the American Ceramic Society,.

59. Nickel, Ernest H. (June 1995). "The definition of a mineral". The

Canadian Mineralogist 33 (3): 689–690. 60. Ph.D. thesis on Local raw material base industries development and

problems A study of Saurashtra region ceramic industries.by Miss. Archna A. Parmar Saurashtra University Rajkot.