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Brilliant
Sparkle, Beautiful and Durable
Gem
Diamond is the hardest and
most brilliant of all precious
gems. The word diamond fills
the mind with images of
a sparkling and dazzling
transparent gemstone, the
incomparable beauty and
purity that has mesmerized
the human mind since ancient
times.

Spectrum of Colors
in Diamond through its Sparkles
Thinking of a diamond brings
a colorless transparent
gem as an image in our mind,
but diamond is actually
found in all colors of spectrum,
ranging from pink, blue,
black, yellow, grey, orange
and even white. Colors of
spectrum belong to certain
energy levels. If these
energy levels are sufficient
to move any electron in
the material to a higher
level, that part of the
spectrum gets absorbed,
and the rest of the light
is emitted out. The presence
of nitrogen atoms in a diamond
crystal absorbs violet and
blue parts of the spectrum,
so the crystal appears yellow.
In a pure carbon crystal,
the spectrum of light has
insufficient energy to move
the strongly bonded electrons
to any level, so no part
of light is absorbed, and
therefore, pure diamonds
are colorless.

Properties of Diamond
Whenever we think of and
hear about diamonds, we
almost always think of diamond
as a gem in jewelry because
of its popularity as a gem,
its stories, fascination
throughout the history including
the ancient history, and
all other amazing facts,
lore and beliefs. However
the utility of diamond is
not limited to it being
just a gem. It is widely
used as an industrial material
and also for scientific
use. Read about its physical
properties below and you
will get to know why we
all have talked about, sought
and fought for diamonds
though the the long history
of diamonds.

Hardness
Diamond is the hardest known
crystalline material composing
mainly of carbon atoms bonded
together by covalent bonds,
each carbon atom bonded
with four other carbon atoms.
This forms a symmetrical
and regular tetrahedral
structure, which imparts
diamond its hardness and
light dispersion properties.
This combination of hardness
and brilliance makes it
popular in jewelry as well
as in industrial applications.
It is the purest form of
carbon.

Diamond’s hardness helps
them against abrasiveness,
as a diamond can be scratched
only by another diamond
or something even harder,
therefore, they retain luster
over long periods of time
and hold a polish extremely
well, that’s why it is preferred
gemstone for engagement
and wedding rings which
are often worn daily.

The hardest diamonds in
the world are found in New
England area in New South
Wales, Australia. The size
of the diamonds found here
is generally small and are
used mostly used to polish
other diamonds. These diamonds
are hardest due to the crystal
formation, which is formed
in a single stage as compared
to other diamonds, which
are formed by multiple growth
stages which leads to more
number of inclusions and
defect planes which affect
their hardness.

The diamond’s hardness also
adds to its utility for
cutting and grinding tools
and abrasives. It can be
used for polishing, cutting
and wearing of other materials
including diamond. Industrial
diamonds are not suitable
to be used as gems and therefore
sometimes synthetically
produced.

Though diamond is the hardest
known material, it is not
surely the toughest one.
Macroscopically it is resistant
to breakage but it can still
be shattered along a few
crystallographic planes,
where the number of bonds
as less as compared to other
directions in the structure,
quite neatly providing perfect
cleavage which comes of
use for diamond cutters.

No Conductivity
Pure diamonds do not exhibit
electrical conductivity,
because there are no free
or lose electrons in its
structure; the carbon atoms
share four electrons of
their outermost shell with
four other atoms to complete
the octet. So there is no
question of any lose electrons
anywhere in its structure.
But if there are inclusions
of some atoms (impurities),
some electrical conductivity
(loosely bound electrons)
is possible as the included
atoms may have more or less
electrons than “four" in
their outermost shell. Diamonds
are electrical insulators,
but the impurities and inclusions
make them work like semiconductors.

Density.
Diamond is denser as compared
to graphite which is also
pure carbon; the only difference
lies in the type of bonding.
Density is the ratio of
mass to volume of a substance.
The density of diamond is
3.51 grams per cubic centimeter
as compared to 2.2 for graphite.
This high density owes to
strong bonds of carbon atoms
formed under high pressure
and temperature conditions
under the earth’s surface.

Though diamond is the hardest
known material, it is not
surely the toughest one.
Macroscopically it is resistant
to breakage but it can still
be shattered along a few
crystallographic planes,
where the number of bonds
as less as compared to other
directions in the structure,
quite neatly providing perfect
cleavage which comes of
use for diamond cutters.

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