Minerals Flashcards
(25 cards)
Define a mineral
naturally occurring inorganic solid with definite chemical composition and regularly repeating atoms
Minerals are made up of
elements
There are how many known minerals
3800
What are 8 different tests to identify minerals
streak, hardness, luster, color, cleavage/fracture, crystal structure, special properties, specific gravity
some minerals are gemstones when…
they are in their crystal form, cut and polished
gemstones are any stone with one of two values
economic or aesthetic
Are all gemstones minerals?
NO
rubies and sapphires come from the mineral
corundum
trace amounts of what turn corundum blue
iron and titanium
what turns corundum pink and deep red ruby
chromium
What minerals are gemstones in their pure form?
diamond, topaz, turquoise
What is the softest of all minerals and what is it used for?
talc used as talcum/baby powder
quarts crystals have a property called
piezoelectricity
What does piezoelectricity mean?
when quartz is placed under mechanical stress, it creates electricity.
What is quartz used in?
clocks, watches, radios
What is halite used for
rock salt on roadways
graphite is used in…
pencil lead
what is the most important ore of lead
galena
galena lead is most commonly used for
lead acid batteries
galena is mined for its….
…silver
what minerals are mined for iron?
magnetite, hematite and limonite
what mineral is used in drywall, cement and plaster of paris
gypsum
what form of gypsum is often used in ornamental pieces–very soft (2)
alabaster
Mohs hardness scale measures what
hardness/softness–the mineral that is hardest will leave scratch on softer mineral
