11.1 Notes Flashcards
Minerals are naturally or unnaturally occuring
naturally
how do minerals form
natural geologic processes
do they have an indefinite or definite chemical composition
definite
how many elements make up most minerals
two or more
are minerals organic or inorganic
inorganic-not living
minerals have what type of crystalline structure
orderly
how are atoms arranged in minerals
orderly and repetitive pattern
a solid body having a visually symmetrical pattern to it’s atomic arrangement
crystals
why do some minerals made of the same element look different
their atoms are arranged differently
minerals are left behind from a body of water when it evaporates ex. sea salt as the water evaporates the mineral halite is left behind
precipitates
what do heat and pressure do
change minerals into new materials
minerals that form out of cooling magma
crystallize
super heated water causes chemical reactions that change minerals into new ones
hydrothermal
what are a mineral’s properties caused by
it’s internal arrangement of atoms
is color a reliable way to identify a mineral
no because many minerals have the same color or one mineral can have many colors
the color of a mineral in it’s powdered form
streak
streak is more or less reliable than color
more reliable because some rocks have a unique color/streak combination
how do you test streak
rub the mineral across a streak plate (a piece of porcelain)
the measure of the resistance of a mineral to being scratched
hardness
how do you test hardness
rub the mineral across a glass plate and look for a groove
hardness is based on
moh’s scale 10 (hardest) to 1 (softest)
which minerals bubble in the presence of acid
calcite and dolomite
the tendency of a mineral to cleave or break along flat even surfaces
cleavage
the uneven breakage of a mineral
fracture
describes how light is reflected from the surface of a mineral
luster
which mineral has a metallic luster
pyrite
which mineral has a non-metallic luster
kaolinite
yellow streak, no cleavage (has fracture) hardness of 2 (soft)
sulfur
rhombohedral cleavage, hardness of 3
Calcite
cleaves in 2 directions at 90 degrees hardness of 6
potassium feldspar
greasy feel, hardness of 1, (very soft) no cleavage has fracture
talc
glassy luster, hardness of 7 (pretty hard) no cleavage (has fracture)
quartz
most common mineral
quartz
what do we classify minerals on
the basis of their chemical composition and observable properties
whats not a good way to identify most minerals
color
the color of a mineral in it’s powdered form
streak
how are a mineral’s chemical properties determined
by their chemical composition (how their atoms are connected)
the ability to scratch another mineral a mineral with a higher number can scratch a mineral with a lower number
hardness
glass has a hardness of
5.5
what is made of minerals
rocks
the tendency of some minerals to break along smooth flat surfaces
cleavage
the uneven breakage of a mineral (the opposite of cleavage)
fracture
how light is reflected from the surface
luster (metallic or non-metallic)
