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| History
The Lore
Gemologically speaking, the diamond is king. The hardest
of all substances, it is the subject of countless legends
and beliefs. One of the more outlandish, and widespread,
beliefs was that diamonds could determine guilt or innocence.
If the accused was guilty, the diamond, acting as judge
and jury, would become darker. In the presence of innocence,
however, it would glow with increased brilliance.
A symbol of innocence, justice, faith, and strength,
the diamond was believed to make its wearers courageous
and victorious over their enemies. When set in gold and
worn on the left side, it held the power to drive away nightmares
and soothe savage beasts. Diamonds were even thought to
be so powerful that they could stop lechery.
Diamonds were believed to sweat in the presence of poison
and were often worn to ward it off, yet believed to be deadly
itself if swallowed. Some people believed that the finest
diamonds could reproduce themselves. Certain exceptional
stones, when moistened with morning dew and left in the
dark, would supposedly produce offspring, though given the
ongoing development of new diamond mines, this technique
probably met with scant success.
The Hindus believed that this brilliant gem was created
when bolts of lightning struck rocks. To be effective as
a talisman, the gem would have to be given as a token of
love or friendship. If bought and sold, it would lose its
powers. April's birthstone is said to be at its most potent
when set in steel.
The Facts
It is the hardest natural substance--four times harder then
the next hardest material, corundum (sapphire and ruby).
As a gemstone, diamond's single flaw (perfect cleavage)
is far outdistanced by the sum of its positive qualities.
It has a broad color range, high refraction, high dispersion
or fire, very low reactivity to chemicals, rarity, and of
course, extreme hardness and durability.
This incredible gem began life about 3 billion years ago
(give or take a million), deep beneath the Earth's surface,
when enormous heat and pressure squeezed together carbon
C atoms into the most atomically dense substance known --
a crystal that, because of its density, is not just transparent,
but is a playground for light.
How much pressure does it take to make a diamond? Imagine
the Eiffel Tower turned upside down, with all its weight
resting on a plate 5 inches square. This is definitely not
something you can make at home.
The diamonds that make it to the surface were forced up
volcanically, to form kimberlite pipes near the surface--like
a gigantic carrot encrusted with diamonds. Once found, it
takes several years to dig up the whole pipe and extract
the diamonds, which can be a whole range of sizes from sandpaper
grade to monsters the size of a human fist.
Diamonds are mined in many parts of the world, but 80% of
the stones on the market today come from Angola, Australia,
Botswana, Namibia, South Africa, Russia and Zaire. All of
these sources might appear to indicate great availability,
but this is not the case. More than 250 tons of ore need
to be blasted, crushed and processed to yield just one carat
of rough diamond. If that weren't enough, most of the rough
extracted from the ground is not suitable for gems; only
about 20% of all rough diamonds are suitable for gems cutting.
They could hardly be called beautiful in the rough--they
look a bit like glass that has been washed up on a beach.
They are ready to be cut and polished -- not an easy task
with the Earth's hardest substance.
Hard as it is, it is not invincible--fortunately for us.
Because it is a crystalline formation, diamond has four
directions of cleavage. If it receives a sharp accurate
blow in one of these directions it will cleave, or split.
If it weren't for this tendency, humans might never have
started cutting diamonds into gemstones.
The first place it goes is to a cleaver or sawyer--depending
on the cleavage of the stone. Their job is to cleave or
cut the diamond into two pieces to bring out the best angle,
establishing what the final cut will be.
Sawing is a lengthy process, whereas cleaving is finished
the instant after the diamond is lit by a sharp blow from
a blade and hammer. However, some stones have too many stress
points and might split into fragments if cleaved, so those
go to the sawyer, who is slow, meticulous and safe--if a
little more expensive.
After the stone has been cleaved or sawed, it goes through
a series of cutters who each have their own specialty. The
blocker cuts out the rough shape of the diamond, and the
brilliandeers, divided into top maker and bottom maker,
cut the table and facets above the girdle and cut the pavilion
respectively. At the end of the cutter line is the girdler,
who cuts the girdle and the facets around it. In many cases
nowadays, these processes can be performed by incredibly
precise computerized machinery, though the top quality stuff
is still done by humans.
Completing the process is the longest step of all: polishing.
Because of their extreme hardness, diamonds can be polished
only by other diamonds, so fine diamond abrasives are used
to create the stone's many angled planes, or facets. Each
facet must be in perfect geometric proportion to every other
in order to provide maximum reflection.
After this, the diamond is ready to be set. The journey
finishes when it finally finds a home with someone who will
wear it for a lifetime. |
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