te-zn-cu sulfuros masivos rusia

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ORIGINAL PAPER

Tellurium-bearing minerals in zoned sulfide chimneys

from Cu-Zn massive sulfide deposits of the Urals, Russia

V. V. Maslennikov & S. P. Maslennikova & R. R. Large &

L. V. Danyushevsky &R. J. Herrington & C. J. Stanley

Received: 21 June 2011 /Accepted: 18 October 2012 /Published online: 22 November 2012# Springer-Verlag Wien 2012

Abstract Tellurium-bearing minerals are generally rare in

chimney material from mafic and bimodal felsic volcanic

hosted massive sulfide (VMS) deposits, but are abundant in

chimneys of the Urals VMS deposits located within Silurianand Devonian bimodal mafic sequences. High physico-

chemical gradients during chimney growth result in a wide

range of telluride and sulfoarsenide assemblages including a

variety of Cu-Ag-Te-S and Ag-Pb-Bi-Te solid solution se-

ries and tellurium sulfosalts. A change in chimney types

from Fe-Cu to Cu-Zn-Fe to Zn-Cu is accompanied by grad-

ual replacement of abundant Fe-, Co, Bi-, and Pb- tellurides

by Hg, Ag, Au-Ag telluride and galen a-fahlore with

native gold assemblages. Decreasing amounts of pyrite,

both colloform and pseudomorphic after pyrrhotite, iso-

cubanite ISS and chalcopyrite in the chimneys is coupled

with increasing amounts of sphalerite, quatz, barite or

talc contents. This trend represents a transition from low-

to high sulphidation conditions, and it is observed across a

range of the Urals deposits from bimodal mafic- to bimodal

felsic-hosted types: Yaman-Kasy Molodezhnoye

Uzelga Valentorskoye Oktyabrskoye Alexandrin-

skoye Tash-Tau Jusa.

Introduction

Tellurium-bearing mineralization is found associated with

many sulfide deposits, particularly in epithermal vein depos-

its of gold and silver (Afifi et al.1988b; Ciobanu et al.2006;

Cook et al. 2007a, b; Jaireth 1991). In general, tellurium-

bearing minerals are relatively uncommon in volca nic-

hosted massive sulfide (VHMS or VMS) deposits (Afifi et

al.1988b; McPhail1995), with the notable exception of the

Urals, where tellurides and tellurium minerals are recordedat a number of deposits (Shadlun 1942; Herrington et al.

1998; Prokin and Buslaev 1999; Moloshag et al. 2002;

Vikentyev2006; Novoselov et al.2006). Tellurium is scarce

in active seafloor hydrothermal systems, and tellurobismu-

thite is recorded rarely in sulfides from the modern oceans

(Iizasa et al.1992).

In the Urals, tellurides are not present in all VMS deposits

(Prokin and Buslaev 1999; Vikentyev 2006). The causes of

this are poorly understood. A theory that tellurides form in

massive sulfide ores during recrystallization caused by late

(low-temperature) hydrothermal or metamorphic processes

(Vikentyev 2006; Eremin 1983) is in contradiction with

the discovery of rich telluride occurrences in some non-

metamorphosed VMS deposits (Shadlun1942; Maslennikov

1999). In previous work (Herrington et al.1998; Maslennikov

et al.1997,2009; Maslennikova and Maslennikov2007), the

authors documented some tellurium-bearing phases in very

well preserved zoned vent chimney fragments from non-

metamorphosed Yaman-Kasy deposit. These results were

highly unusual, but more recently, numerous sulfide chimneys

from a number of unmetamorphosed VMS deposits of the

Editorial handling: L. Danyushevsky

V. V. Maslennikov (*)

Institute of Mineralogy, Ural Devision of RAS,

and the South Ural State University,

Miass, Chelyabinsk district, Russia

e-mail: [email protected]

S. P. Maslennikova

Institute of Mineralogy, Ural Division of RAS,and the South Ural State University,

Miass, Chelyabinsk district, Russia

R. R. Large : L. V. Danyushevsky

CODES ARC Centre of Excellence in Ore Deposits and School

of Earth Sciences, University of Tasmania,

Hobart, Australia

R. J. Herrington : C. J. Stanley

Department of Mineralogy, Natural History Museum,

Cromwell Road,

London SW7 5BD, UK

Miner Petrol (2013) 107:6799

DOI 10.1007/s00710-012-0230-x
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Urals have been discovered and are presented here. Diverse

tellurides are abundant in some chimneys but absent in others.

These conflicting data create numerous questions and require

an explanation. The problem can be resolved by research at

different scales including analysis of relevant genetic features

of host sequences, systematic textural and paragenetic studies

of different types of VMS deposits and chimneys, and their

rare mineral assemblages. Paragenetic models, compositionalanalyses and ranges of tellurium-bearing minerals and the

physicochemical interpretation of chimney diversity in differ-

ent types of VMS deposits are the main subjects of this paper.

Methods and samples studied

A preliminary mineralogical study of the samples was fol-

lowed by scanning electron microscopy (REMMA2M

SEM equipped with energy dispersive Xray detector and

JEOL JXA 733) at the Institute of Mineralogy, Russian

Academy of Sciences. Further mineral analyses wereobtained in several laboratories equipped with CAMEBAX

SX50 and JEOL-JXL-8600 (Natural History Museum,

London), Cameca SX-100 (University of Tasmania, Aus-

tralia) and JEOL JXA 8900RL (Freiberg Mining Academy,

Germany). Analytical conditions were similar in the differ-

ent laboratories. In all electron microprobe analyses, the

standard deviation of results is less than 0.1 %. Major and

minor elements were determined at 1525 kV accelerating

potential , 2035 nA beam current and acquisition time

between 10 and 20 s for Xray peak and background. The

effective probe size was between 1 and 2 m.. The follow-

ing standards were used: SK (ZnS), AgL (Ag), SbL

(Sb2S3), CdL(CdS), TeL (Bi2Te3), TeLb (Ag2Te), SeK

(PbSe), BiL(Bi2Te3), PbL(PbS), CuK (CuFeS2), SK

(Bi2S3), AgL (Ag), SbL (Sb2S3), CdL (CdTe), SeK

(Bi2Se3), BiL(Bi2S3), HgMa (HgS) AsKa (GaAs), Cd La

(CdS), MnKa (Mn), CoKa (FeCoNi), TlMa (TlInS2). De-

tection limits were commonly within the following range

(wt%): S and Fe 0.06. Co 0.05, Ni 0.08, Cu 0.10, Zn

0.14, As 0.12, Ag 0.15, Sb 0.090.2, Te 0.120.29,

Hg 0.22, Au 0.18, Pb 0.190.34, Bi 0.180.26, Se

0.10.13, Sn 0.030.05, Hg 0.10.3, Tl 0.27, Sn 0.03,

Mn 0.04.

Quantitative analysis of chimney sulfides and tellurides

for a wide range of major and trace elements (Fe, Cu, Zn,

Co, Ni, Au, Ag, Bi, Pb, Tl, Cd, As, Te, Se, Mo, Sn, V, Ti,

and Mn) was carried out using LA-ICPMS. The instrumen-

tation includes a New Wave 213 nm solid-state laser micro-

probe coupled to an Agilent 7500cs quadrupole ICPMS

housed at the CODES LA-ICPMS analytical facility, Uni-

versity of Tasmania.

The laser microprobe was equipped with an in-house small

volume (~ 2.5 cm3) ablation cell characterised by


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Yaman-Kasy) are ascribed to either a marginal sea (Zaykov

2006) or an island arc (Herrington et al.2005b). The Tagil

and Magnitogorsk zones include a range of arc, back- and

intra-arc rifts (Herrington et al.2005b; Zaykov2006). In the

Sakmara and Tagil arcs, the VMS deposits are hosted in

Silurian age basalt-rhyolite complexes whilst those in the

Magnitogorsk zone are Devonian. The VMS deposits are

situated in extensional graben or half-graben rift valleysnot only in back-arc basins, but also in intra-arc rifted

basement (Maslennikov 1999). The intra-arc rifts contained

infrequently developed calderas (Seravkin 2010). Most of

VMS deposits are located within several stratigraphic levels

(Fig.2).

Urals VMS deposits have been subdivided as into four

main types: Cyprus, Uralian, Besshi and Baymak (note that

names such as Kuroko-type and Altai-type have also

been used in the lite rature to describe the latter type),

depending on the geological and geodynamic conditions of

formation (Glasby et al.2006; Gusev et al.2000; Herrington

et al. 2002, 2005a; Prokin and Buslaev 1999; Seravkin2010; Zaykov2006). These types can be broadly compared

to the classification of Franklin et al. (2005) where Cyprus0

Mafic, Besshi0Pelitic-mafic, Uralian0Bimodal-mafic, and

Baymak0Bimodal-felsic. The Urals VMS deposits where

chimneys were identified are related to the Uralian or

Baymak types. The Uralian and Baymak type deposits

can be subdivided based on the distance between the ore

bodies and basalt basements (Table 1). The distances are

roughly correlated with general ore mineralogy and Te

contents in ore bodies and in the chimneys studied.

The chimneys in situ were found in the central part of

orebodies interpreted as the relics of hydrothermal sulfideFig. 1 The locations of the Urals VMS deposits with documented

chimney occurrences

Fig. 2 The locations of chimney-bearing Urals VMS deposits in compiled stratigraphic columns

Tellurium-bearing minerals in zoned sulfide chimneys 69
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mounds degraded on the seafloor (Fig.3). The central part of

the ore lens consists of compact pyrite-chalcopyrite ores

consequently flanked by sulfide breccias and sulfide

turbidites intercalating with ferruginous cherts or black

shales (Maslennikov 1999, 2006; Herrington et al. 2005b;

Buschmann and Maslennikov 2006; Maslennikov et al.

2009). The clastic ores and in-situ massive sulfides collected

from the apex of the sulfide mounds contain abundant frag-

ments of well-preserved chimneys and occasional sulfidized

fauna (Little et al.1997). The lens-like shape of the ore bodies

and the presence of clastic ore with vent fossils indicate that the

Urals VMS deposits were ancient analogues ofblack smoker

sulfide mounds (Shadlun 1991; Zaykov et al. 1995). The

discovery of black smoker chimney fragments confirmed this

hypothesis (Herrington et al.1998; Maslennikov1991,1999,

2006; Maslennikov et al.2009).

Typical features of the Uralian type VMS deposits are a)

common colloform and biomorphic textures of pyrite, relic

Table 1 Te contents in the bulk ore (Data from open reports of

Ministry of Base Metals, USSR) and chimneys (original data by ICP-

MS and LA-ICP-MS analytical techniques) from different types of the

Urals VMS deposits and chimneys (original data from Zaykov 2006;

Maslennikov1999; Moloshag et al. 2002; Tessalina et al.1998,2008;

Vikentyev et al.2000,2004)

VMS Deposit Types Distance from

basalt basement (m)

Mean Te in

ore (ppm)

Mean Te in

chimneys

(ppm)

General ore mineralogy

Yubileynoye Cyprus to

Uaralian

0 30 40 Pyrite, chalcopyrite, sphalerite, marcasite, pyrrhotite,

arsenopyrite, magnetite, tennantite, hessite, and

electrum

Yaman-Kasy Uralian 0100 325 1349 Pyrite, marcasite, chalcopyrite, sphalerite, bornite,

marcasite, arsenopyrite, pyrrhotite, altaite,

tellurobismuthite, coloradoite, empres, site, galena,

site, hessite, tennantite, barite, hematite and magnetite,

galena, enargite, petzite, sttzite, lllingite, volynskite,

greenockite, digenite, cervelleite, benleonardite,

covellite, goldfieldite, sylvanite, frohbergite,

native tellurium, native gold, magnetite

Molodezhnoye Uralian 30120 82 1030 Pyrite, chalcopyrite, sphalerite, bornite, marcasite,

arsenopyrite, pyrrhotite, altaite, tellurobismuthite,

coloradoite, empressite, hessite, tennantite, barite,

hematite, and magnetite, galena, enargite,

stromeyerite, arsenosulvanite, jalpaite, mackinstryite,stannoidite, mowsonite, native gold

Uzelga-4 Uralian 40150 110 358 Pyrite, chalcopyrite, pyrrhotite, altaite,

tellurobismuthite, sylvanite, petzite, coloradoite,

shttzite, hessite, native tellurium, native gold,

tennantite, tetrahedrite, magnetite, arsenopyrite,

coloradoite, siderite,

Oktyabrskoye Uralian to

Baymak

200 30 166 Pyrite, chalcopyrite, bornite, digenite, sphalerite,

quartz, bornite, barite, hessite, altaite, tennantite,

tetrahedrite, native gold

Valentorskoye Uralian to

Baymak

90300 28 196 Pyrite, chalcopyrite, bornite, hessite, tellurobismuthite,

sttzite, empressite or kochkarite, tennantite,

cervelleite, wittichenite, renierite, native gold

Alexandrinskoye Baymak 310 39 28 Pyrite, chalcopyrite, sphalerite, bornite, barite, galena,

tennantite, , hessite, diagenite, stromeyerite, renierite,germanite, acantite, pyrseite, native gold and electrum

Tash-Tau Baymak 150300 5 25 Pyrite, sphalerite, and chacopyrite, bornite, tennantite,

galena, hessite, cervellite, native gold, and electrum,

enargite, galena, digenite, stromeyerite, jalpaite,

germanite, calcite, barite

Saphyanovskoye Baymak or Altai >300 1 17 Pyrite, chalcopyrite, sphalerite, pyrrhotite, galena,

tennatite, tetrahedrite, glauckodot, tellurobismuthite,

hessite and unresolved Bi-telluride, enargite,

stannite, native gold, Pb-sulfosalts

1

Jusa Baymak to

Kuroko

>300 3 0.1 Pyrite, chalcopyrite, sphalerite, galena, tennantite,

tetrahedrite, arsenopyrite, native gold

70 V.V. Maslennikov et al.
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phyrrhotite, pseudomorphs of pyrite and marcasite after initial

euhedral pyrrhotite, b) common occurrence of isocubanite

intermediate solid solutions (ISS) and c) low-sulfidation con-

ditions of formation, indicated by the presence of altaite. In the

Baymak-type VMS deposits, colloform and biomorphic pyrite

occurrences are rare, whereas pyrrhotite and pseudomorphs

after pyrrhotite are absent. In the footwall of the Baymak-type

deposits, volcanics are commonly highly altered to quartz-

sericite and sometimes pyrophyllite assemblages with scat-

tered pyrite, chalcopyrite, sphalerite and galena, which form

economically important ores. Abundant galena and fahlores

suggest moderate- to high-sulfidation condition for Baymak-

type deposit formation.

Preservation of chimney material

In the Magnitogorsk and Sakmara zones, the VMS deposits

have been affected by low grade metamorphism, typically to

prehnite-pumpellite facies only. The good preservation of

primary colloform, sulfidized fauna and chimney textures of

the ores is due to this low degree of metamorphic overprint

(Herrington et al.1998; Little et al.1997; Maslennikov et al.

2009; Shadlun 1991; Zaykov 2006). Further north in the

Urals, the rocks of the Tagil arc are dominated by volcanic

units strongly metamorphosed from greenschist to granulite

facies. The Tagil arc, which contains magnetite-rich ferrugi-

nous sediments, is generally metamorphosed to greenschist

facies. Chimney fragments were not found in the Tagil arc,

Dombarovsk and Orsk areas, where the VMS deposits are

metamorphosed to epidote-amphibolite facies. Two excep-

tions to this are the recovery of sulfide chimneys from the

Valentorskoye and Saphyanovskoye deposits. The latter only

shows zeolite facies metamorphism (Grabezhev et al.2001),

and a similar of metamorphic grade is also assumed for the

Valentorskoye deposit. These deposits are located in tectoni-

cally preserved fragments of less-metamorphosed terrains.

Recovery of chimney material is thus restricted to speci-

mens from less metamorphosed VMS deposits, which are

comparable in textural features to modern black and gray

smokers (Herrington et al.1998). In the core of the sulfide

mounds, chimneys are variably recrystallized to granular

pyrite. The most diverse and well-preserved fragments of

sulfide chimneys are instead found within ore breccias. In

sulfide turbidites, the primary colloform and sooty pyrite

fragments of the chimneys were replaced by diagenetic

chalcopyrite, granular pyrite and cryptocrystalline hema-

tite due to seafloor oxidation (Saphina and Maslennikov 2008)

Fig. 3 The position of sulfide

chimneys in the ore bodies from

the Urals VMS deposits

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Results

Mineral zonation of chimneys studied

Previous papers have described three Urals chimney frag-

ments where there was clear evidence for high-temperature

fluid flow through the axial zone, passing to a temperature-

zoned chimney wall (Herrington et al. 1998; Maslennikov1999). These authors recognized the presence of three broad

mineralogical zones developed in response to the interaction

of high-temperature vent fluid with seawater.

Chimneys can be broadly divided into three radial

zones described here from the outer wall, formerly in

contact with seawater, to the inner axial hydrothermal

flow cavity: A - external zone typified by pyrite,

marcasite and/or sphalerite; B - internal zone typified

by the presence of chalcopyrite, and C - lining of the

axial zone normally infilled by sphalerite, quartz or

barite. Each of thes e zones may be subdivided into

several subzones in each sample, depending on thepresence of other minerals.

Our new work based on more than 200 well-preserved

chimney/conduit fragments also shows that we can broadly

classify the chimney into 3 types based on mineralogy

(Figs.4 and 5):

Type 1: chalcopyrite-pyrite to quartz-pyrite-chalcopyrite;

Type 2: chalcopyrite-pyrite (marcasite)-sphalerite to quartz-

sphalerite-pyrite-chalcopyrite barite;

Type 3: chalcopyrite-sphalerite to barite-sphalerite-chalcopyrite;

The types form a general range with an increase of

sphalerite abundance from type 1 to type 3. In each type,

the mineralogical variations lead to a decrease in chalcopy-

rite accompanied by an increase in either quartz + pyrite

(type 1 in Fig. 4ad), or sphalerite + quartz (type 2 in

Figs. 4ehand 5ac), or sphalerite + quartz + barite (type

3 in Fig. 5dh). Each type or subtype of these chimneys

exhibits specific mineralogical zonation, loosely adhering to

the broad A, B, C zones classification indicated above.

Mineralogical and textural proxies of the zonation can be

found in the segments of chimney walls (Figs.6,7,8). Each

type of the chimneys contains different rare mineral assemb-

lages (Table2).

Type 1 chimneys

Numerous fragments of chalcopyrite-pyrite chimneys are

present in the Yubileinoye deposit, but the most com-

plete range from chalcopyrite-pyrite to quartz-pyri te-

chalcopyrite chimneys was found in the Yaman-Kasy

deposit. Other type 1 chimney fragments occur in the

lower part of the Saphyanovskoye ore body, and rarely

at the Molodezhnoye, Uzelga-4 and Valentorskoye

deposits. The largest piece of a chimney recovered

measures some 4 cm in diameter and is 12 cm long.

Another typical fragment was found in the sulfide brec-

cia layer on the southern flank of the massive sulfide

lens, measuring some 3-5 cm in diameter, about 4-8 cm

long, and is very strikingly zoned. In cross-section, all

fragments have a simple 23 fold zonation with the

development of A, B and C zones.

Zone A In the chimneys from the Yaman-Kasy deposit, the

outermost zone is composed of laminated and botryoidal

colloform pyrite and the orientation suggests a centrifugal

growth of the botryoidal pyrite (Figs. 6a and 7ac).

Fig. 4 Type 1 (ad) and Types 23 (eh) chimneys specimens from

Yaman-Kasy deposit. Type 1 chimneys: a chalcopyrite-pyrite, b

chalcopyrite-pyrite-marcasite-sphalerite, c marcasite-chalcopyrite-

pyrite-quartz, d quartz-pyrite-chalcopyrite. Type 2 and 3 chimneys:

e chalcopyrite-pyrite-sphalerite; f chalcopyrite-sphalerite-pyrite-

marcasite, g sphalerite-chalcopyrite-marcasite, h quartz-sphalerite-

barite-pyrite-chalcopyrite. a, b, c chimney structural zones (see text

for details). Scale is 1 cm

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Colloform pyrite grades to a vuggy, fine to medium

grained pyrite towards the central part of zone A (sub-

zone A2). The outer layers in the chimneys from the

Saphyanovskoye deposit are made up of botryoidal,

framboidal and dendritic pyrite partly replaced by chal-

copyrite (Fig. 7df). In subzone A2 (Fig. 7a, c, f), there

are rare disseminated tabular-hexagonal crystals of either

nonstochiometric cryptocrystalline pyrite or fine-grained

marcasite, replacing an initial subhedral pyrrhotite

phase. This texture has been also described in modern

chimneys (Peter and Scott 1988; Marchig and Rsch

1988; Paradis et al. 1988), in ores of the Uralian type

deposits (Maslennikova and Maslennikov 2007), and in the

ancient chimney fragments (Maslennikov et al. 2009). The

pseudomorphs contain relic inclusions of pyrrhotite and dis-

play incomplete cleavages in the pyrite, characteristic of for-

mer pyrrhotite crystals (Zhabin and Samsonova1975). Pyrite

net veining and porous textures are typical of pyrite pseudo-

morphs after pyrrhotite crystals (Zierenberg et al. 1993). Chal-

copyrite abundance increases towards the inner rim of zone A

(subzone A3), where idiomorphic coarse-grained pyrite is the

main phase. Euhedral pyrite can contain inclusions of

pyrrhotite. Sphalerite and marcasite are rare to absent in

subzone A3 of chalcopyrite-pyrite chimneys but are abundant

in quartz-rich varieties. The boundary between zones A and B

is distinctive, marked by the disappearance of the granular

aggregates of pyrite.

Fig. 5 Type 2 (ac) and Type 3 (dh) chimneys from the Uselga (a),

Molodezhnoye (b), Saphyanovskoye (c, d), Valentorskoye (e, f), and

Alexandrinskoye (g, h) VMS deposits. a chalcopyrite-pyrite-

sphalerite-quartz, b chalcopyrite-pyrite-sphalerite, c chalcopyrite-

quartz-pyrite-marcasite, d sphalerite-pyrite-chalcopyrite, e

chalcopyrite-sphalerite-quartz, f quartz-sphalerite-pyrite-chalcopy-rite; g sphalerite-chalcopyrite-barite, h sphalerite-chalcopyrite. a,

b, c chimney structural zones (see text for details)

Fig. 6 The most important microfabrics of the chimneys studied:

Yaman-Kasy (af), Oktyabrskoye (g) and Alexandrinskoye (h) deposits.

Reflected lighta reniform colloform pyrite from the outer wall; b

marcasite pseudomorphs after tabular pyrrhotite crystals in the central

part of the outer wall;c subhedral and euhedral pyrite at the boundary

with the chalcopyrite wall;d drusy chalcopyrite with isocubanite lattice;

e kidney-shaped chalcopyrite segregations within sphalerite frame, and

disseminated lllingite in the transition zone between the wall and the

channel; f marcasite pseudomorphs after tabular pyrrhotite crystals in

the sphalerite cement of the channel; g sphalerite with disseminated

chalcopyrite of the outer wall at the contact with crustified chalcopy-

rite of the wall; h graphic intergrowth of chalcopyrite and sphalerite

in the channel

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Zone B The interior of the chimneys is formed by rhythmic

layers of coarse-grainedbladeddrusy chalcopyrite (Fig.7).

In chalcopyrite-pyrite chimneys, the outer part (subzone B1),

close to the boundary with zone A, contains cubic crystals of

pyrite only (Yubileynoye, Yaman-Kasy deposits) and is de-void of accessory minerals (Fig. 4a). Sulphoarsenides or/and

tellurides occur in chalcopyrite-pyrite-quartz transitional

members of the series.

In the Saphyanovskoye deposit, glaucodot occurs in such

chimneys whilst in the Valentorskoye deposit, the chimneys

contain Pb-rich tellurobismuthite. Chalcopyrite-pyrite-quartz

chimneys from the Molodezhnoye deposit contain altaite. In

the Yaman-Kasy deposit, the quartz-chalcopyrite-pyrite

chimneys contain disseminated frohbergite, altaite, Sb-rich

tellurobismuthite, sylvanite, sttzite and coloradoite which is

Fig. 7 Wall zonation of type 1 chimneys from the Urals VMS deposits

Fig. 8 Wall zonation of type 2 chimneys from the Urals VMS depos-

its. For legend see Fig. 7

Table 2 Accessory minerals in the chimneys from the Urals VMS

deposits

Minerals Types of VMS deposits

Uralian Baymak

Yb Y S M U V O A TT

Pyrrhotite Fe9S8 + + +

Co- and Te-rich lllingite

(Fe0.8Co0.2)(As1.5Te0.4S0.1)

+

Cobaltite CoAsS +

Arsenopyrite FeAsS + +

Glaucodot (Fe,Co)AsS +

Frohbergite (Fe, Co)Te2 +

Altaite PbTe + + + +

Tellurobismuthite Bi2Te3 + + +

Sylvanite AgAuTe4 + +

Petzite AuAg3Te2 +

Coloradoite HgTe + +

Sttzite Ag5Te3or-phase Ag1.88Te + +

Hessite Ag2Te + + + + + + + +

EmpressiteAgTe + +

Volynskite AgBiTe2 +

Native tellurium Te + +

TeO + Te or Te.H2O +

Native gold Au0.8Ag0.2 + + + + + + + +

CuAg-sulfotellurides +

(CuAgHg)-sulfosalts + +

Tennantite

Cu10(Zn,Fe)2(As,Sb,Te)4S13

+ + + + + + +

Tetrahedrite

Cu10(Zn,Fe)2(Sb,As,Te)4S13

+ + + +

Goldfieldite Cu10Te4S13 +

Greenockite CdS +

Bornite Cu5FeS4 + + + +

Galena PbS + + + + + +

Copper sulfides CuSCu2S + + +

Magnetite FeOFe2O3 + +

Hematite F2O3 +

Deposits: Yb Yubileynoye, Y Yaman-Kasy, V Valentorskoye, M

Molodezhnoye, U Uzelga, O Oktyabrskoye, SSaphyanovskoye, A

Alexandrinskoye,TTTash-Tau

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partly replaced by As, Cu, Ag-sulfosalts (e.g., (Cu,Ag)3AsS4)

related to the enargite group. In quartz-pyrite-chalcopyrite

end-members, tetrahedrite, tennantite and native gold

are common minerals. In the subzone B2, the coarse-

grained chalcopyrite crystals rarely contain pyrite and

accessory mineral assemblages. These are commonly

found in subhedral chalcopyrite crystals of subzone B3.

Zone CThis axial conduit zone is poorly developed in the

chalcopyrite-pyrite chimneys. The position of the axial con-

duit is marked by subhedral marcasite and pyrite or fram-

boidal pyrite (Fig. 7). The open channels located in the

centre of the chalcopyrite-pyrite-quartz and quartz-pyrite

chalcopyrite chimneys are subsequently infilled with subhe-

dral pyrite, marcasite and quartz. In quartz-rich conduits,

tetrahedrite, tennantite, digenite, and bornite occur in asso-

ciation with relics of chalcopyrite.

Type 2 chimneys

The chimneys range from chalcopyrite-pyrite-sphalerite

chimneys to quartz-sphalerite-pyrite-chalcopyrite barite

varieties and are most abundant in the Uralian type of the

VMS deposits (Yaman-Kasy, Uzelga-4, Molodezhnoye, and

the lower level of Saphyanovskoye). Chimneys 210 cm in

diameter and 515 cm long were recovered. Three zones

and several subzones are present in this chimney type

(Figs.4c, dand8).

Zone A This zone shares features with type 1 chimneys. In

chalcopyrite-pyrite-sphalerite chimneys, the outermost sub-

zone A1 is dominated by laminated and botryoidal collo-

form pyrite with interstitial quartz and marcasite (Fig. 8).

However, in some chimneys from the Baymak type deposits

(e.g., Valentorskoye) aggregates of recrystallized dendritic

pyrite are predominant (Fig.8g, h). The fine-grained pyrite

is often quite porous and may be replaced and overgrown by

coarse marcasite. In the middle part (subzone A2), granular

aggregates of pyrite and marcasite enclose very rare pseu-

domorphs after subhedral pyrrhotite (Figs. 6band 8a, b, c,

e). Tetrahedral crystals of chalcopyrite, iron-free sphalerite

and sparry marcasite successively form an epitaxial incrus-

tation on relics of fine-grained colloform pyrite. The cores

of some sphalerite crystals contain emulsion-like chalcopy-

rite forming chalcopyrite disease described in sphalerite

from modern black smoker chimneys (Herrington et al.

1998; Shadlun 1991). The amount of colloform pyrite and

its pseudomorphs after pyrrhotite decline with the increase

in sphalerite at the outer wall of the chimneys. The outer

wall of the sphalerite-rich end-members of this range con-

tains mainly globular colloform, framboidal or/and dendritic

pyrite disseminated in sphalerite and cryptocrystalline quartz

(Maslennikov et al.2009). Colloform pyrite is partly replaced

by anhedral sphalerite, chalcopyrite or quartz in the innermost

part of the zone. Towards the inner part of the outer wall,

coarse-grained marcasite is replaced by euhedral pyrite

enclosed in a chalcopyrite and/or quartz matrix (Fig. 6c). A

galena-tennantite-tetrahedrite assemblage is common for sub-

zones A2 and A3. In the Molodezhnoye deposit, veinlets of

altaite were found in colloform pyrite of pyrite-chalcopyrite-

sphalerite chimneys.

Zone B This zone can be divided into two or three parts

(Fig. 8). The first part (subzone B1) consists of medium-

grained massive or laminated chalcopyrite. Some of the chal-

copyrite layers intercalate with thin interlayers of sphalerite

and/or quartz. Subhedral pyrite, marcasite and accessory min-

erals are common in this subzone. Subzone B2 is composed of

coarse-grained bladed inclusion-free chalcopyrite. This sub-

zone is usually broader in the chalcopyrite-pyrite-sphalerite

members of this chimney type but is commonly absent in the

quartz-sphalerite-pyrite-chalcopyrite barite end-members.

Subzone B3 comprises spear-shaped crystals of chalcopyritewith inclusions of disseminated pyrite and accessory minerals.

In the B1 and B3 subzones, relicts of tartan isocubanite struc-

tures are occasionally observed (Fig. 6d), as was previously

described at Yaman-Kasy (Herrington et al. 1998; Shadlun

1991). Some chimneys from the Molodeznoye, Yaman-Kasy

and Saphyanovskoye deposits contain inclusions of pyrite

pseudomorphs over euhedral pyrrhotite crystals.

In chalcopyrite-pyrite-sphalerite chimneys from the

Yaman-Kasy deposit, subzones B1 and B3 contain telluro-

bismuthite, occasional altaite, frohbergite and sylvanite.

Abundant and diverse rare mineral assemblages are com-

mon in sphalerite-chalcopyrite-pyrite varieties of the

chimneys. Also present are successive overgrowths of co-

baltite, altaite, sylvanite, sttzite, volynskite, native telluri-

um, unresolved black-brown oxide-rich tellurium phases,

and galena. Petzite, empressite, coloradoite and tellurian

lllingite are present occasionally. Tellurobismuthite and

frohbergite are rare, confined to the boundaries with sub-

zone B2. In some chimneys, Ag-sulphotellurides or fine-

grained unresolved Ag-Te-S micrographic phases are found.

A later assemblage comprises native tellurium and gold,

covellite, galena and a newly identified Cu, Pb, Ag, Fe

arsenic-tellurium sulphosalt phase with an approximate for-

mula (Cu, Pb, Hg, Ag,Fe)3 (As,Te)S4. Galena and other

sulphosalts occur together in the outermost part of subzone

B1 and the innermost part of subzone B3. These sulphosalts

replace sulphoarsenides, tellurides, and galena. Mineral di-

versity declines in the barite-rich end member of type 2

chimneys. These quartz-sphalerite-pyrite-chalcopyrite

barite end-members of the chimney range contain mostly

very small grains of hessite, native gold, galena, volynskite,

and tennantite, which are confined to the boundaries be-

tween chalcopyrite and sphalerite. Altaite, arsenopyrite, and

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native gold were found in association with hessite, galena

and tennantite in zone B of chalcopyrite-sphalerite-pyrite type

chimneys from the Molodezhnoye deposit. Chalcopyrite-

pyrite-sphalerite-quartz barite chimneys from the Uzelga-4

deposit contain disseminated coloradoite, and very small

grains of tellurobismuthite and gold-rich silver telluride

(probably hessite). In the Saphyanovskoye deposit, small

grains of tellurobismuthite and hessite in association withglaucodot and arsenopyrite have been found. Sulphoarsenides

are replaced by tennantite and tetrahedrite. Tellurides and

arsenides have been replaced by a native gold galena -

tennantite association in sphalerite-pyrite-chalcopyrite

chimneys, found at the upper level of the Saphyanovskoye

deposit. At the boundary with zone C, lllingite occurs in

chalcopyrite, sphalerite and quartz (Fig.6e).

Zon e C The conduits of chalcopyrite-pyrite-sphalerite

chimneys are successively in-filled by pyrite, marcasite, sphal-

erite and occasional quartz (Fig. 8). Quartz-sphalerite-pyrite-

chalcopyrite barite chimneys are characterized by anincreased amount of galena, quartz and euhedral barite.

Sphalerite shows extensive chalcopyrite diseaseand also a

texture consistent with being a pseudomorph after wurtzite

(Herrington et al.1998). Pseudomorphs of marcasite or pyrite

after pyrrhotite are also present in this zone (Fig. 6f). In the

chimneys from the Yaman-Kasy deposit, goldfieldite occurs

in association with a quartz-marcasite assemblage. In the

chimneys of all other deposits, sphalerite-galena-tennantite

assemblages are more common.

In chalcopyrite-pyrite-sphalerite chimneys, the Co- and

Fe-sulfoarsenides and Fe, Co, Bi, Pb-tellurides are replaced

successively by native gold and hessite, and then galena-

sulfosalts assemblages with generally increasing contents of

sphalerite, quartz and barite. The quartz-sphalerite-pyrite-

chalcopyrite barite end-members of this chimney type

resemble the type 3 chimneys.

Type 3 chimneys

This chimney type ranges from chalcopyrite-sphalerite to

quartz-sphalerite -chalcopyrite barite varieties. The main

differences from the previous types are the absence of

marcasite and pyrite pseudomorphs after pyrrhotite. Pyrite

occurs as minor inclusions of euhedral, subhedral pyrite.

Colloform varieties of pyrite are very rare.

Fragments of type 3 chimneys have been collected from

the Alexandrinskoye, Tash-Tau, Jusa , Oktyabrskoye, Val-

entorskoye and Talganskoye deposits. The chimneys are

commonly 2-4 cm in diameter and up to 8 cm in length,

with the largest fragment measuring 10 cm in diameter and

16 cm in length. Mineralogical zones defined from the

exterior to the interior in this type of chimneys are described

below and shown on Fig.9

Zone A The outer wall of this zone comprises predominantsphalerite with disseminated euhedral and subhedral pyrite

(Fig.6g). Barite, quartz, galena and tennantite inclusions are

common for this zone. Rare colloform or framboidal pyrite

occurs only in the outermost subzone of the chimneys. Most

of the original colloform pyrite is replaced by chalcopyrite,

tennantite and galena.

Zone B This chalcopyrite-rich zone is formed by drusy

aggregates of chalcopyrite crystals, successively overgrown

by sphalerite (Fig.6h). The chalcopyrite layers are intercalat-

ed with sphalerite. In chalcopyrite-sphalerite chimneys from

the Valentorskoye deposit, the chalcopyrite contains small

disseminated grains of Pb-rich tellurobismuthite, rare empres-

site and sttzite. In the central parts of this type, hessite and

native gold intergrowth occurs in association with chalcopy-

rite, pyrite, sphalerite and galena. In sphalerite-rich varieties

of these chimneys, galena and Te-rich tennantite are common

mineral inclusions. In the chimneys from the Oktyabrskoye

deposit, chalcopyrite contains rare inclusions of altaite, gale-

na and euhedral pyrite. Chalcopyrite from other deposits is

devoid of accessory minerals. Some chimneys from the Alex-

andrinskoye deposit contain bornite inclusions in association

with euhedral pyrite.

Zone C The conduit zone consists of sphalerite, quartz and

barite. In the Oktyabrskoye deposit, sphalerite contains tellur-

obithmuthite, altaite, galena, and hessite inclusions in associ-

ation with native gold. Galena-tennantite intergrowths in

association with native gold occur in sphalerite of the

chimneys, veinlets and conduits from both Alexandrinskoye

and Tash-Tau deposits (Maslennikova and Maslennikov 2007;

Zaykov 2006). Rare hessite in association with native gold has

been found in sphalerite chimneys from the Alexandrinskoye

Fig. 9 Wall zonation of type 3 chimneys from the Urals VMS depos-

its. Chimneys (d) to (f) are intermediate between Types 2 and 3. For

legend see Fig.7

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deposit. Sphalerite-barite-chalcopyrite chimneys from the

Jusa deposit contain galena and tennantite only.

Composition of tellurium-bearing phases

Te-bearing sufides

We have used SEM and LA-ICP-MS techniques to investigate

the distribution of Te in the chimneys. The most detailed data

were collected by high-resolution LA-ICP-MS analyses of the

Yaman-Kasy deposit (Maslennikov et al.2009). In this paper

we present average contents of Te in chalcopyrite, sphalerite

and pyrite in each main zone of the chimneys from other Urals

VHMS deposits (Table 3). A small number of bornite and

galena grains have also been analyzed by LA-ICP-MS.

Chalcopyrite (CuFeS2) Chalcopyrite is an important host

mineral for Te. The concentrations of Te in chalcopyrite of

the chimneys vary over several orders of magnitude be-tween deposits: Yubileynoye (2560 ppm) Yaman-Kasy

(303200) Uzelga-4 (10250 ) Molodezhnoye (10

2050) Valentorskoye (5550) Octyabrskoye (440)

Alexandrinskoye (


12/34

Table3

MeanTecontentsinsulfid

esfromeachzoneofeachchimneytype(ppm)

Deposit

Chimneytyp

e

Azone

Bzone

Czone

Py

Chp

Sph

Py

Chp

Sph

Py

Ch

p

Sph

Yubileynoye

2

59.1

(16)

0.4

(1)

3.2

(7)

24.3

(6)

3.5

(10

)

23.4

(5)

7.7

(7)

8.7

(2)

4.0

(2)

1

29.7

(12)

2.0

(5)

52.8

(2)

34.3

(10

)

6.8

(2)

186.2

(10)

63.2

(6)

10.0

(5)

1

37.5

(10)

5.9

(3)

57.0

(6)

5.0

(7)

22.0

(1)

Oktyabrskoye

3

281.7

(7)

40.0

(2)

232.4

(5)

693.3

(1)

3.9

(7)

364.7

(2)

103.0

(1)

3.6

(2)

92.7

(4)

TashTau

3

119.0

(9)

0.9

(5)

66.8

(2)

0.1

(12

)

0.0

4(1)

22.4

(3)

0.1

(1)

3

42.4

(5)

0.7

(3)

38.4

(6)

1.5

(9)

3.2

(11)

90.9

(2)

0.4

(3)

6.6

(6)

Valentorskoye

23

160.1

(6)

33.4

(3)

223.5

(2)

1541.6

(5)

41.2

(13

)

296.0

(5)

166.6

(5)

3

67.1

(5)

23

150.0

(9)

5.3

(4)

18.2

(4)

25.7

(14

)

15.7

(5)

127.2

(5)

6.7

(3)

23

440.0

(7)

34.2

(2)

46.0

(2)

405.5

(6)

18.4

(10

)

148.8

(9)

11.6

(1)

22.3

(4)

2

555.7

(8)

541.2

(6)

78.4

(3)

138.7

(8)

52.4

(8)

2

40.2

(2)

38.6

(6)

Molodezhnoye

2

17.9

(7)

1047.9

(8)

616.5

(4)

10734(5)

20

61.9

(1)

412.4

(5)

2

620.2

(14)

17.2

(1)

16.5

(4)

1007.4

(1)

344.7

(12

)

11.2

(1)

360.4

(4)

2

1651.0

(4)

799.5

(3)

218.6

(5)

960.0

(8)

802.5

(3)

7.1

(2)

154.3

(11)

Saphyanovskoye

3

34.3

(7)

2.8

(5)

7.9

(1)

1.0

(3)

0.1

(1)

54.1

(1)

1.3

(3)

4.5

(5)

2

5.9

(14)

0.8

(2)

0.6

(3)

5.0

(4)

27.0

(10

)

19.8

(1)

3.3

(3)

2

21.2

(12)

1.9

(2)

0.5

(1)

17.8

(6)

30.4

(16

)

0.2

(1)

3.5

(5)

4.8

(11)

Uzelga

2

1192.2

(16)

10(8)

24.3

(7)

179.5

(18)

188.3

(14

)

22.4

(6)

476.3

(8)

2

49.0

(6)

64.2

(3)

Alexandrinskoye

2

46.0

(8)

0.4

(5)

27.2

(15

)

3.7

(3)

26.0

(2)

24.7

(9)

1

161.8

(3)

1.3

(3)

14.6

(8)

88.2

(7)

0.5

(11)

0.8

(4)

20.8

(3)

29.3

(6)

16.2

(7)

Jusa

3

0.2

(21)

0.2

(12)

0.2

(2)

0.0

(6)

0.1

(2)

0.3

(1)

YamanKasy

1

28.8

(34)

25.4

(7)

47.0

(8)

32.1

(15

)

26.0

(6)

1/0(3)

2

530.0

(13)

73.2

(7)

465.1

(4)

1585.7

(22

)

15.0

(4)

3849.0

(6)

67

58.5

(13)

38.0

(20)

2

167.1

(20)

19.6

(8)

863.1

(7)

3194.5

(8)

102.3

(3)

21587(3)

3

78.1

(9)

818.6

(2)

54.5

(6)

3603.2

(5)

28837(4)

411.8

(1)

1652.9

(4)

27

48.5

(4)

1205.2

(10)

3

2052.1

(13)

51.9

(10)

838.0

(14)

73.3

(11)

20.4

(4)

11.5

(3)

Numberofanalysesisshowninbra

ckets.

mineralisabsent.AnalyseswerecarriedoutattheUniversityofTasmania(Ho

bart,Australia)



13/34

(Table6). Possible substitutions of As and S for Te are also

inferred from our data. Extensive mixing between lllingite

and isostructural tellurides: mattagamite, melonite and

frohhbergite has been described by Ciobanu et al. (2008).

Te-rich cobaltite-like mineral Co(S,AsTe)2 (Fig. 10d).

This mineral occurs as relics of small pink cubic crystals

included in native tellurium. Commonly, grains of the

cobaltite-like mineral are corroded and replaced by other

tellurides, making their analysis by a microprobe virtually

impossible. Contents of Te in the mineral are up to 12-15 wt.

%. The calculated formula is Co1.0(As0.7Te0.2)S1.1. Some of

the high grades of Te are, probably, caused by tellurides and

native tellurium micro-inclusions. Rare homogenous areas

within this mineral, as observed in back-scattered SEM

images, were used for analysis, revealing minor amounts

of Cu, Fe, Zn, and Sb (Table 6). Their small size prevents

any crystallographic studies to determine the structure of

this mineral. The mineral merits further investigations.Te-containing gl aucodot (C o0.48 Fe0.57Cu 0.12)1.12

(As1.14Te0.02)1.16S (Table 6). Small white grains (< 5 m) have

been found in chalcopyrite-rich chimneys of types 1 and 2

in the Saphyanovskoye deposit. Glaucodot is commonly

associated with hessite and the late-formed tennantite and

tetrahedrite. High Fe contents may be due to isomorphic

series of allocrasite-glaucodot-arsenopyrite. Some grains

contain elevated Cu (411 wt. %) suggesting isomorphism

between glaucodot and lautite (CuAsS) series in the micro-

inclusions of tennantite. The elevated contents of Te (0.6

1.4 wt. %) and Ag (0.21.5 wt. %) may be due to either

substitution of Te for As, or micro-inclusions of hessite.

Pb-, Bi- and Pb-Bi tellurides and related minerals

Altaite (PbTe) is by far the most common telluride present,

usually in the form of dispersed 2-3 m grains. Larger

grains (up to 2 mm) are found adjacent to later galena in

the narrow part of zone B in type 2 chimneys from the

Yaman-Kasy and Molodezhnoye deposits (Fig. 10a, d). In

conduits of type 3 chimneys from the Oktyabrskoye deposit,

altaite occurs in sphalerite as intergrowths with hessite and

galena. Successive overgrowths and replacement of altaite

by sttzite-hessite, native tellurium and galena are common

(Fig.7d). The altaite is slightly non-stoichiometric, containing

an excess of Te. Other trace elements in altaite include Sb and

Ag (Table 4), with the likely substitution2b2+Ag1+ + Sb3+.

Altaite has high concentrations of Au, Bi and Ag. This is

consistent with published data, where altaite was also identi-

fied as a Au carrier (Ciobanu et al. 2009b; Vikentyev2006).

High concentrations of Co and As are due to micro-inclusions

of the cobaltite-like mineral.

Tellurobismuthite (Bi2Te3). Pink-white platty ctystals of

tellurobismuthite (Fig. 10b) occur in the outer and inner

parts of zone B within the chalcopyrite-rich chimneys of

types 1 and 2 in the Yaman-Kasy and Valentorskoye depos-

its (Fig.7a). Tellurobismuthite contains no S (Table 7), and

is similar to occurrences of this mineral in both pyrrhotite

and chalcopyrite-pyrite ores of Uralian type VMS deposits

(Sibai, Uchaly), which contrasts with bismuth sulfotellurides

found in galena-sphalerite-rich ores of the Baimak type VMS

deposits (Moloshag et al.2002). An excess of Te is noted in

the tellurobismuthite measured here as compared with

the theoretical formula. In the quartz-pyrite-chalcopyrite

chimneys from the Yaman-Kay deposit, Sb contents reach 7.1

Fig. 10 Reflected light photomicrographs of tellurium mineralization

in the chimneys from the Yaman-Kasy (ad, g, h), Valentorskoye (e),

Oktyabrskoye (f) deposits. a coloradoite (Cld) in association with

altaite (Alt) and frohbergite (Frb) in chalcopyrite (Cp);b tellurobis-

muthite (Tbs) at the boundary of the chalcopyrite (Cp) wall with the

sphalerite (Sl) channel; c sylvanite (Syl) twins with chalcopyrite (Cp)

in the sphalerite (Sl) matrix; d telluride mineralization (volynskite (Vol),

altaite (Alt), hessite (Hs), cobaltite (Cob), native tellurium (Te)) in asso-

ciation with sulfides (galena (Gn), marcasite (Mrc), chalcopyrite (Cp) and

sphalerite (Sl)) and quartz (Qz); e hessite (Hs) in association with

tellurobismuthite (Tbs) or kochkarite-like minerals, galena (Gn) and gold

(Au);fnative gold (Au) with hessite (Hs), tetrahedrite (Td) and galena

(Gn)in sphalerite (Sl); g crystals of goldfieldite (Gld) in quartz (Qz); h

myrmekitic intergrowths of native tellurium (Te) and silver thiotellurite

sulphosalt (Sfs)

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wt. %, where it substitutes for bismuth. Measured Sb and Bi

contents are consistent with experimental data for ternary

system BiSbTe (Caillat et al. 1992). Elevated contents of

Cu, S and Fe (Table 7) are likely due to analytical overlapcaused by the small grain size.(Table8)

Kochkarite-like ISS(Ag-Pb-Bi-Sb-Te intermediate solid

solution) occurs in chalcopyrite of zone B of pyrite-sphalerite-

chalcopyrite chimneys in the Valentorskoye deposit. Silver-

white platy crystals of these minerals are associated with sphal-

erite, hessite, galena and native gold, but not with altaite

(Fig.10e). The values of Pb are highly varied in the minerals

(Table 7). Substitution of minor Pb for Bi is widespread

throughout the group of Bi-tellurides (Cook et al. 2007b). The

phases can be considered as members of the alexite group

(Cook et al.2007a). However the most of compiled results of

analyses display the continuous compositional range from tel-

lurobismuthite to ruckligeite, not overlapping with the tsumoiteand tetradymite-aleksite ranges (Fig.11a, b). Contents of S and

Se are also low in the kochkarite-like minerals.

The most varieties of the kochkarite-like minerals have

Te contents within 5659 at. %. Some of those are probably

akin to the synthetic layered compounds with formula

PbBi6Te10 and PbBi8Te13. The series of structurally related

compounds, in close compositional proximity to one anoth-

er, can be potentially stacked in a disordered manner. These

c o m p o u n d s m a y b e l o n g t o a h o m o l o g o u s s e r i e s

Table 4 Chemical composition of tellurides from the low-sulphidation assemblages in the Type 2 and 3 chimneys from the Urals VMS

deposits (wt. %)

Frohbergite

N D Ag Te Sb Fe Co Se Tl Pd Total Formula

1 Y 82.17 0.59 12.66 4.97 0.25 100.64 (Fe0.69Co0.26)0.95(Te1.98Se0.01Sb0.01)2

2 81.70 0.62 12.99 4.49 0.19 99.99 (Fe0.72Co0.23)0.95(Te1.97Se0.01Sb0.02)2

3 81.82 0.68 12.78 4.98 0.22 100.48 (Fe0.70Co0.26)0.96(Te1.97Se0.01Sb0.02)2

4 81.87 0.64 13.32 4.23 0.19 100.25 (Fe0.73Co0.22)0.95(Te1.97Se0.01Sb0.02)2

5 81.96 17.98 99.94 Fe1.00Te2.00

6 82.04 17.86 99.90 Fe1.00Te2.00

7 81.82 18.09 99.91 Fe1.01Te2.00

Coloradoite

N D Ag Te Sb Hg Bi Se Tl Pd Total Formula

8 Y 39.82 59.00 0.44 0.30 99.56 (Hg0.94Tl0.03Pd0.01)0.98Te1

9 39.94 60.13 0.54 0.16 100.77 (Hg0.96Tl0.04Pd0.01)1.01Te1

10 39.80 61.04 0.39 101.14 (Hg0.98Pd0.01)0.99Te1

11 0.07 40.78 0.55 56.88 2.13 0.09 100.50 (Hg0.87Bi0.03)0.90(Te0.99Sb0.01)1

12 0.16 37.86 0.32 61.84 0.10 0.08 100.36 Hg1.03(Te0.99Sb0.01)1

13 U

38.28

61.13

99.41 Hg1.02Te114 38.97 60.91 99.88 Hg0.99Te1

15 38.53 60.83 99.36 Hg1.00Te1

Altaite

N D Ag Te Sb Pb Co Se Tl Pd Total Formula

16 Y 0.34 38.09 0.30 60.22 99.20 (Pb0.97Ag0.01)0.98(Te0.99Sb0.01)1

17 0.34 39.01 0.24 60.44 0.08 100.12 (Pb0.95Ag0.01)0.96(Te0.99Sb0.01)1

18 0.44 37.76 0.27 61.25 99.94 (Pb0.99Ag0.01)1.00(Te0.99Sb0.01)1

19 0.19 38.12 0.00 61.03 99.34 (Pb0.99Ag0.01)1.00Te1.00

20 M 37.54 62.39 99.93 Pb1.02Te1

21 37.72 62.25 99.97 Pb1.02Te1

22 38.14 61.64 99.78 Pb1.01Te1

23 O

38.12

61.18

99.30 Pb0.99Te1

24 1.87 38.77 59.02 99.65 (Pb0.94Ag0.03)0.97Te1

25 37.36 62.42 99.78 Pb1.03Te1

D VMS deposits: Y Yaman-Kasy; U Uzelga; M Molodezhnoye; O Oktyabrskoye; V Valentorskoye. element has not been analysed.

Analyses were carried out: 14, 11, 12, 16, 17 by JEOL JXA 8900 RL (the University of Tasmania, Hobart, Australia); 57, 1315, 2025 inby

REMMA-2 M SEM (the Institute of Mineralogy of UB RAS), 810 inby Camebax SX50 (NHM, London, England); 1819 in JEOL JXA

8900 RL (Freiberg Mining Academy, Freiberg, Germany)

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Table5

Traceelementconcentratio

ns(ppm)inaccessorymineralsfromthepa

leo-hydrothermalchimneys(LA-ICP-MS)

N

Minerals

Te

Bi

Ag

Au

Fe

Pb

Cu

Zn

As

Se

V

1

Tellurobismuthite(9)

mean

459409

490000

4709

2.5

1

4406

30568

4640

375

2.5

4

5189

31.2

4

max

495619

542000

7491

8.0

7

21639

48294

23984

1976

6.2

1

5971

103.7

0

min

404833

431000

3014

0.3

3

64

16745

25

0

0.5

2

4358

0.2

3

2

Sylvanite(2)

621000

6.9

7

130536

217269

13444

10

16767

136

0.2

8

te-zn-cu sulfuros masivos rusia

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