FROM THE DEPTHS
as
pointed in the rear as it does in the front—and it does in the front
because it must constantly be pushing against almost invulnerable
objects. Thus, even the most rounded stones that appear are somewhat
pointed, such as the tetrakishexahedron, which has curved faces, the
hexakisoc-tahedron, which also has curved faces but is more rounded,
and the twinned or spinel octahedrons. They either are "diamond-shaped"
or show definite signs of liking for that shape.
This
theory is questioned by most authorities, since they believe that the
diamond crystallized long before it erupted from the fiery heart of the
earth. This explains its cleavages and grains)
Now
this is how scientists describe it and, even so, I am paraphrasing
their descriptions. (Quoted sources are A. C. Austin and Marion Mercer
of the Colorado School of Mines, and L. J. Spencer, Editor of the
Mineralogical Magazine of London and formerly Keeper of Minerals in
the British Museum and Honorary Life Fellow of the Mineralogical
Society of America.) They say:
You
have the carbon atoms lined up in the stone in definite patterns. Most
of the minerals in nature assume a definite crystal shape because of
such an alignment. The crystal shapes of the diamond all belong to the
"isometric" or cubic system, which has the most perfect symmetry known.
The eight-sided figure is the most common shape in diamonds, although
other more complex crystals ate sometimes found having as many as
forty-eight sides. Perfectly shaped crystals, however, are the
exception rather than the ,rule. The arrangement of the carbon atoms in
a diamond was first determined about twenty years ago. Diamonds were
photographed with a special X-ray apparatus
(9)
