Minerals: Importance: mineral->rock->solid earth; natural material for inorganic industrial
manufactures; the products of minerals are in our everyday life (glass, metal, salt, gemstone,
pencil lead, etc.)
: Inorganic solid, naturally occurring, ordered internal molecular structure.,
characteristic chemical composition, They are the building blocks of the rocks. Rock:
aggregates of one or more minerals.
s: caused by the crystalline structure and chemical composition of
(most noticeable but least reliable): dark, light, colorless;
: transparent (clear),
translucent (foggy), opaque (impervious to light)
Crystal form/ Habit
: geometric shapes. Habit: characteristic crystal form of a mineral
: how light reflect from the surface of a mineral: metallic and non metallic. Exposed
surface of metallic minerals will tarnish or weather to a dull or earthy luster, like old coins.
(Fig. 3.5, 3.6 on the lab manual)
: resistance to scratching. Harder substance can scratch softer one.
Mohs Scale of
: using ten minerals as reference for relative hardness (from soft to hard: talc,
gypsum, calcite, fluorite, apatite, orthoclase, quartz, topaz, corundum, diamond);
minerals; >5.5 hard minerals
; hardness of common objects:
fingernail (2.5), penny coin
(3.5), wire nail (4.5), glass (5.5), streak plate (6.5)
. If a mineral’s hardness is between 2.5
and 6.5, you need to minimize the range, e.g. about 5. If greater than 6.5 or smaller than 2.5,
you can just put >6.5 or <2.5 because we have no other measurements to test in the lab.