properties of minerals. hardness - resistance to being scratched mohs hardness scale mohs hardness...
TRANSCRIPT
Properties of MineralsProperties of Minerals
Hardness - resistance to being scratched
Mohs Hardness ScaleMohs Hardness Scale ranges from 1(talc) to 10 ranges from 1(talc) to 10
(diamond)(diamond)
a mineral will only scratch a mineral will only scratch those softer than itthose softer than it
Field scaleField scale common test using fingernail common test using fingernail
(1), penny (3), glass (6)(1), penny (3), glass (6)
Color- not a reliable indicator of identity due to weathering and
impurities
Look at the 2 fluorite samples.
Streak – the colored powder left when rubbed against a hard surface (more reliable than color because streak is not affected by weathering)
Luster: ability to reflect light on its surfaceglassy metallicsubmetallic nonmetallic
Cleavage & Fracture: the way a mineral breaks when stressed
Cleavage: the tendency to break along flat surfaces and smooth lines (along weak bonds)
Fracture: the quality of the break; typically uneven along curved or irregular surfaces if
mineral’s atomic bonds are strong
Crystal Shape – the natural growth of a mineral
Taste: certain minerals like halite (salt) and sulfur have characteristic flavors (only water soluble minerals
do)
Specific gravity: the ratio of an object’s density to the density of water
Magnetism: Magnetite has magnetic properties
Reaction to Acid: an acid, such as hydrochloric acid (HCl), can cause a mineral to fizz
Fluorescence: Calcite and fluorite can glow under UV light.
Optical properties: Calcite can create a double image
Idioms to Ponder
Back to the salt minesBack to the salt mines
Sitting on a gold mineSitting on a gold mine
the need to return to work or some activity that is not fun
in control of something valuable