Mineral or Rock

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Mineral or Rock??? A mineral can be defined as a
naturally occurring inorganic solid that
possesses an orderly internal structure and a
definite chemical composition. Some people, like
physicists, might be guilty of picking up a rock
and calling it a mineral. The term "rock" is less
specific, referring to any solid mass of mineral
or mineral-like material. Common rocks are often
made up of crystals of several kinds of minerals.
Lutgens and Tarbuck give the following list of
essential characteristics of a "mineral" 1.
It must occur naturally. 2. It must be
inorganic 3. It must be a solid 4. It must
possess an orderly internal structure, that is,
its atoms must be arranged in a definite
pattern. 5. It must have a definite chemical
composition that may vary within specified
limits."
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Emerald is the mineral beryl with substitution
defects of Cr(3) or V(3) replacing
Al(3). Beryl has the chemical composition
Be3Al2(SiO3)6 and is classified as a
cyclosilicate. It is the principal ore for the
element beryllium.
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Tsavorite is a variety of the mineral garnet a
calcium-aluminosilicate with the formula
Ca3Al2Si3O12. Crystal form is cubic. Trace
amounts of vanadium or chromium provide the green
color. It is often called the Rolls-Royce of
greens at Cadillac prices. From a collectors
perspective, tsavorite is 200 times more rare
than emerald, it is cleaner, more brilliant and
not oiled or treated in any way.
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Tourmaline is a large group of aluminosilicate
minerals, with variable composition (Ca,K,Na)(Al,
Fe,Li,Mg,Mn)3(Al,Cr,Fe,V)6(BO3)3(Si,Al,B)6O18(OH,F
)4 Elbaite is one of the forms found as pink and
green colors, having the general formula
Na(Li,Al)3Al6(BO3)3Si6O18(OH)4. It is a silicate
with lithium content, a relatively rare element.
Crystal forms are trigonal.
Tourmaline Nature's source of Negative Ions
Is that why its in my hairbrush???
Tourmaline is one of the naturally pyroelectric
minerals. Pyroelectronic charge in minerals
develops on the opposite faces of asymmetric
crystals.
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Peridot is the gem-quality form of the mineral
Olivine. It has the chemical composition
(Mg,Fe)2SiO4, with Mg in greater quantities than
Fe. The depth of green depends on how much iron
is contained in the crystal structure, and varies
from yellow-green to olive to brownish green.
Peridot is also often referred to as "poor man's
emerald". Olivine is a very abundant mineral, but
gem-quality peridot is rather rare. Peridot
crystals have been collected from some Pallasite
meteorites
Polarized micrograph
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Quartz - SiO2 -simplest silicate mineral,
piezoelectric, chiral!
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Replace -S with I -Zn with Hg (at
vertices) -Zn with Ag (in middle)
Replace -S with I -Zn with Hg (at
vertices) -Zn with Cu (in middle)
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