| |
I INTRODUCTION
Diamond is a mineral form of carbon, used for various industrial purposes,
and also valued as a precious stone. Diamonds occur in various forms
including ballas, bort, carbonado, and the diamond proper (a crystalline
gemstone). Ballas is a compact, spherical mass of tiny immensely
hard diamond crystals. Bort is an imperfectly crystallized diamond,
extremely hard, and dark in color. The term bort also sometimes
refers to minute fragments of gem diamonds. Carbonado, sometimes called
black diamond or carbon, takes an opaque grayish or black form. Carbonado,
ballas, and bort are all used industrially as the edges of drills and
cutting tools.
II PROPERTIES
Diamond is the hardest substance known and is given a value of 10 in the
Mohs hardness scale, devised by the German mineralogist Friedrich Mohs to
indicate relative hardness of substances on a rating scale from 1 to 10.
Its hardness varies in every diamond with the crystallographic direction.
Moreover, hardness on the same face or surface varies with the direction
of the cut.
Diamond crystallizes in different forms. Eight and twelve sided
crystal forms are most commonly found. Cubical, rounded, and paired
crystals are also common. Crystalline diamonds always separate
cleanly along planes parallel to the faces. The specific gravity for
pure diamond crystals is almost always 3.52. Other properties of the
diamond are frequently useful in differentiating between true diamonds and
imitations: Because diamonds are excellent conductors of heat, they are
cold to the touch; Most diamonds are not good electrical conductors
and become charged with positive electricity when rubbed; Diamond is
resistant to attack by acids or bases; Transparent diamond crystals
heated in oxygen burn at about 1470° F, forming carbon dioxide.
Diamonds vary widely in color and transparency. Color in diamonds is
caused by the presence of minor elements. Diamonds of clear, strong,
and unusual color are highly valued. Colorless stones, known as white
diamonds, are extremely valuable, while yellow or brown tinged stones are
regarded as imperfect. Green and blue diamonds are rarities and red
diamonds are the rarest of all.
Diamond gems are also valued for luster and fire. Both of the
physical properties that determine luster and fire, (the index of
refraction and the dispersion), are higher for diamond than for any other
natural, transparent, colorless stone. Uncut diamonds have a hazy
luster and are not brilliant, but when cut, the stones exhibit a high
luster, know technically as adamantine. The effect of the proper cut
is high dispersion, which is the separation of the colored components of
white light so that the stone sparkles. Some diamonds exhibit
luminescence when exposed to sunlight or other ultraviolet-light sources.
The color is usually light blue, but yellow, orange, milky white, and red
luminescence may occur in some stones.
III MARKETS
Diamond markets are supplied by global sources. For centuries,
India, was the only known source of diamonds in the world. Today,
production in India is limited to small quantities. The greatest
diamond field in the world today is in the area of the Orange River in
South Africa where diamonds were first found in1866. Diamond
deposits have been found in other parts of Africa, including Tanzania, the
Democratic Republic of the Congo, Ghana, and Sierra Leone. Discoveries
have also been made in Australia, Brazil, Borneo, Canada, Guyana, the Ural
Mountains, and Venezuela. Most Brazilian diamonds are used for the
production of ballas and carbonado. Diamond stones have been found
at various places in the United States, and a deposit in Arkansas yields
diamonds, though not in quantities sufficient for profitable excavation.
IV INVESTING
Diamonds are the world's most compact, concentrated and portable hard
asset. Pound for pound, a top quality diamond can be 10,000 times
more valuable than gold. Because diamonds are resilient,
portable, inconspicuous, and highly valuable, they have taken on a role as
a safe haven asset used to preserve wealth from the detrimental effects of
financial instability. Diamonds possess three sought after
advantages over paper assets and some other hard assets: |
|
