How are diamonds transformed from rough to polished?
A rough diamond obtains its final shape and brilliance by a succession of manufacturing
processes : cleaving or sawing, bruting and polishing.
How is the quality of a diamond defined?
The quality of a diamond is determined by the Four C's. Carat weight, Colour, Clarity and Cut.
A diamond can be graded for quality in a certificates laboratory HRD Certificates Lab. How are diamonds mined?
Mining methods are very diverse, depending on how
diamonds present themselves at the earth's surface. Mining
of Kimberlite pipes involves "open-pit" or "underground
mining". When freed by erosion from the Kimberlite matrix,
diamond crystals are carried along by rivers. Riverbeds are
dug away and the river silt is sieved. This technique is
called "alluvial mining". "Coastal mining" is the exploitation
of sandy coastal strata by dredging?. Finding diamonds can
thus be the result of large industrial operations, but also of
small-scale methods, or even manual labour. Diamonds are
rare. It is usual that 250 tons of rock, sand and gravel must be processed to yield one carat of
polished diamond. The annual world production amounts to approximately 120 million carats of
which only around 60% are of gem quality depending on the market for polished diamonds.
What is a carat?
Diamonds are weighed in carats. One carat equals a fifth of a gram. The name "carat" comes
from a seed of the carob tree. The seed was called "carubis" and had an approximate weight of
about 0.2 grams.
Why is craftsmanship in diamond processing so important?
A diamond can be loupe clean and have the best white colour, but if the facets of the stone
have not been placed in perfect harmony, then there is no shine, no fire in the stone. The label
"Cut in Antwerp" is a quality label referring to the best diamond cut in the world.
Which are the most famous diamonds in the world?
The Cullinan I:a pear shaped diamond of
530.20 carats also called "The Great Star
of Africa". Set in the English Crown
Jewels. Can be admired in the Tower of
London.
The Koh-I-Noor: This "Mountain of Light"
is the oldest of the famous diamonds, has
an oval shape and weighs 105.60 carat.
Discovered in India, the stone is now part
of the Crown Jewels in the Tower of
London.
The Hope: This is a blue diamond of
45.52 carats with a remarkable brilliance. At the moment, the stone is on display at the
Smithsonian Institution in Washington.The diamond had the reputation of bringing misfortune.
What is the economic importance of Antwerp as World Diamond Center?
Antwerp is situated in the heart of Europe, easy to reach by car, plane or train. The diamond
center is concentrated on two square miles near the Central Railway Station.
Over 50 pct of the world production, be it rough or polished, industrial or gem quality diamonds,
passes through Antwerp.
What is a Diamond?
Diamond, the hardest known natural material is pure carbon,
crystallised under very high pressure and temperature. In nature,
such an environment exists only at depths of 150 to 200 km below
the surface of the earth. Volcanic eruptions drive the diamond
bearing rocks called magmas to the surface of the earth where they
cool and harden to form' Kimberlite and Lamproite' or from which
the diamonds can be extracted.
Where can I buy diamond jewelry?
Diamond Jewelry Central.Com
Where are the main diamond sources?
Throughout history people have
always been fascinated by the beauty
and mystery of diamonds. Until the
18th century, when diamonds were
discovered in Brazil, India was the
only source of diamonds in the world.
In the second half of the 19th century,
the first diamonds were discovered in
South Africa and soon after a
"diamond rush" started. The first
diamond diggers worked individually
by hand, but when the pits became
deeper large mining companies were
established, exploiting the diamond mines with mechanical equipment.
Today, the most
important diamond supplying countries are Australia and Congo for industrial diamonds and
Botswana, Russia, South Africa Namibia, Canada and Congo for gem quality stones.