Color:
All colors.Diamonds most commonly occur in shades of yellow, gray and brown. The rarer stones
are colorless and the rarest are reds, blues, pinks, greens in
intense saturation.
Clarity: Transparent
to opaque
Optic Character: SR
Cause
of Color:
Yellow
and Orange: Ni and related color centers
Blue:B
Green: Color centers due tonatural or artificial irradiation
Red, Pink, Brown: Unknown
Fluorescence: Inert to
strong
Fracture
: Step-like
Luster : Adamantine
Cleavage : Four
directions; perfect
Durability: Diamonds
are the hardest of all gemstones. That refers to their ability
to scratch. But they can be broken along their four planes of
inherent cleavage.
Characteristics
for Identification:
Naturals
on the girdle, thermal inertial higher than simulants, bearding
on girdle, adamantine luster
Localities:
Diamond deposits are found world
wide. The most noteable being
Africa, Australia, India and
most recently Canada.
Diamond
is a polymorph (many forms) of the element carbon. Graphite
is another polymorph. The two share the same chemistry, pure
carbon, but have very different structures and properties.
Diamond is hard, Graphite is soft (the "lead" of
a pencil). Diamond is an excellent electrical insulator, Graphite
is a good conductor of electricity. Diamond is the ultimate
abrasive, Graphite is a very good lubricant. Diamond is transparent,
Graphite is opaque. Diamond crystallizes in the Isometric
system and graphite crystallizes in the hexagonal system.
Somewhat of a surprise is that at surface temperatures and
pressures, Graphite is the stable form of carbon. In fact,
all diamonds at or near the surface of the Earth are currently
undergoing a transformation into Graphite. This reaction,
fortunately, is extremely slow. |
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Diamonds
have long been valued for their hardness and incredible brilliance.
Chemically a diamond is pure carbon, just like the graphite
used in pencils. Diamonds' hardness is the result of extremely
strong chemical bonds between the carbon atoms. Although most
people think of diamonds as colorless, they actually occur in
almost every color. Diamonds were viewed as talisman by the
ancient Hindus in India, which is where diamonds were first
discovered. The most powerful stones were thought to be naturally
occurring octahedrons of exceptional clarity that exhibited
fire. These stones would bring the owner power, wealth, everlasting
youth and good fortune. It was believed that flawed or inclusive
stones could have quite the opposite effect. During the first
century AD prominent Romans wore uncut diamonds set in rings
also as talismans. For hundreds of years it was believed that
diamonds had gender. As late as 1566, Francois Ruet described
two diamonds as having offspring. The first diamond engagement
ring was given to Mary of Burgundy by Maximillian in 1477.
More
Interseting Diamond Notes:
Clarity: diamond is transparent over a larger range of wavelengths
(from the ultraviolet into the far infrared) than is any
other substance
Thermal
Conductivity: diamond
conducts heat better than anything - five times better than
the second best element, Silver!
Melting Point: diamond has the highest melting point (3820
degrees Kelvin)!
Lattice
Density: The atoms of diamond are packed closer
together than are the atoms of any other substance!
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