Tue 1/19
1. What is a mineral?
Minerals are naturally occurring
They are not made by humans
Minerals are inorganic
They have never been alive and are not made up from plants or animals
Minerals are solids
They are not liquids (like water), or gases (like the air around you)
Minerals have a definite chemical composition
Each one is made of a particular mix of chemical elements
Minerals have an ordered atomic arrangement
The chemical elements that make up each mineral are arranged in a particular
way - this is why minerals 'grow' as crystals
Crystal – the atoms that make up the mineral
are arranged in a particular pattern.
Physical Properties of Minerals
(can be used to identify the mineral)
Luster
• Surface reflection
• metallic = shiny like
metal
• non-metallic = dull,
non-shiny surface
Pyrite has a metallic luster
Calcite has a non-metallic luster
Physical Properties of Minerals
(can be used to identify the mineral)
Hardness
• How easily a mineral scratches
materials
• Mohs Hardness Scale
• Scale from 1 (softest) to 10 (hardest)
• Test by seeing if the mineral can scratch
different objects (like human fingernail, copper,
penny, glass, steel file)
Wed 1/21
2. What is a “Carat”?
One carat weighs 200 milligrams, or one-fifth
(.2) of a gram. This standard has been in use
worldwide since 1914, when it was proposed by
the International Committee on Weights and
Measures.
Fri 1/22
3. Name the mineral.
Can be scratched by
Topaz but not Feldspar.
Quartz
Mon 1/25
What happens when a mineral breaks?
Tue 1/26
Why is a minerals streak more reliable than color?
Streak is the same , even if different color.
Thur 1/27
How do minerals form?
What is the difference between a rock and a
mineral?
Fri 1/22
3. Name the mineral.
Can be scratched by
Topaz but not Feldspar.
Quartz
Physical Properties of Minerals
(can be used to identify the mineral)
Color
• Can be misleading
• Can vary with the type of impurities
Physical Properties of Minerals
(can be used to identify the mineral)
Streak
• The color of the powdered
form of the mineral
• The color of the streak can be
different than the mineral
• Minerals must be softer than
the streak plate
Physical Properties of Minerals
(can be used to identify the mineral)
Luster
• Surface reflection
• metallic = shiny like
metal
• non-metallic = dull,
non-shiny surface
Pyrite has a metallic luster
Calcite has a non-metallic luster
Mon 1/25
What happens when minerals break?
How do minerals form?
• 1) Cooling of magma (hot, liquid rock and
minerals inside the earth (from the
mantle))
– Fast Cooling = No Crystals (mineraloids)
– Medium Cooling = small crystals
– Slow Cooling = large crystals
• 2) Elements dissolved in liquids (usually
How
do
minerals
form?
water)