identifying minerals inside earth chapter 4.1 pages 121-126
DESCRIPTION
Color Color Color is an easily observed physical property. Not the best property to use to identify because many minerals like quartz can come in a variety of colors.TRANSCRIPT
Identifying Minerals
Inside Earth Chapter 4.1Pages 121-126
Identifying Minerals
Crystal Systems
Cleavage/Fracture
Special Properties
Density
Hardness
Color
Streak
Luster
Color
• Color is an easily observed physical property. Not the best property to use to identify because many minerals like quartz can come in a variety of colors.
Streak
• Streak is the color of the mineral’s powder when it is rubbed against a Streak Plate – This property does not vary like the color of
the mineral can.
Luster
• Metallic luster- looks like a metal.
• Non-Metallic Luster does not look like a metal: can be glassy, dull, earthy, waxy and pearly.
• Luster is used to describe how a mineral reflects light from its surface.
Crystal Structure
• Each mineral grows atom to atom to form that mineral’s particular structure.– Classified into six groups (crystal systems) based
on the number and angle of the crystal faces.
Cleavage• Cleavage - is a mineral that easily splits along
flat surfaces.
Fracture
• Fracture - describes how a mineral looks when it breaks apart in an irregular way.
Special Properties
• Fluorescence- glows under UV (ultraviolet light)
• Magnetic- acts like a magnet• Radioactive- give off radiation- Uraninite• Reacts to Acid- reacts by fizzing.• Electrical Properties- electric current can be
produced (Quartz)– Used in watches
• It is the mass in a given volume.
• It always remains the same for any given mineral.
Density
MD Vx
• A balance would be used to measure the mass of a sample.
• The sample can be placed in a graduated cylinder to determine the volume.
Density
• Water Displacement (how much water is moved, is equal to the volume of the sample) is used to determine the volume of the sample
Density
• One of the best clues.• Mohs hardness scale to rank hardness.
– A scale from 1 to 10.
Hardness
Mohs Hardness Scale
Other Hardness’s
4. 5.
A steel nail can easily scratch it.
A steel nail can scratch it.
1. 2. 3.
Softest known mineral.
Flakes when scratched by a fingernail.
A fingernail can easily scratch it.
Fingernail cannot scratch it, but a
copper penny can.
Mohs Hardness Scale6.
10.
Other Hardness’s
7.
8. 9.
Can scratch steel and hard glass easily.
Can scratch quartz. Can scratch topaz.
Can’t be scratched by a steel nail, but can
scratch window glass.
Hardest known mineral, can scratch all other surfaces.
Mineral Hardness Rating
Talc 1Gypsum 2Calcite 3Fluorite 4Apatite 5
Feldspar 6Quartz 7Topaz 8
Corundum 9Diamond 10
What to Work On
• Read textbook pages 118-126• Answer Section Review questions 1-4
on page 126
DUE: Thursday, October 20th