these
the Indian and Arabian, of such indomitable, unspeakable hardness,
that when laid on the anvil it gives the blow back in such force as to
shiver the hammer and anvil to pieces. It can also resist fire, for it
is incapable
of being burnt.....This superiority over steel and
fire
is subdued by goat's blood, in which it must be soaked when the blood
is fresh and warm ; then only when the hammer is wielded with such
force as break both it and
the anvil, will it yield.....Only a god could have
communicated
such a valuable secret to mankind. When at last it yields by means of
the blood, it falls into such small pieces that they can scarcely be
seen."
The
curious opinions of the Ancients as to the infran-gibility of the
Diamond are discussed by Sir Thomas Browne, in his famous work on
"Vulgar Errors,'' written in 1646. The doctor is naturally led to
discard the old views, notwithstanding the support which they had
received from the early Christian writers, and to conclude, on the
evidence of practical diamond-cutters, that Diamonds " are so far from
breaking hammers, that they submit unto pistillation, and resist not an
ordinary pestle." As a matter of fact the Diamond is so brittle that it
is readily reduced to grains, or powder, by pounding in a steel mortar.
Hardness
is the best test of the genuineness of a Diamond. If a mineral cannot
be scratched or cut by Ruby or Sapphire, it must be a Diamond. It is
true that certain bodies, like Carborundum, recently formed in the
electric furnace, are harder than Ruby or Sapphire ; but these are not
minerals.
It
is notable that the hardness of the Diamond varies in different
crystals, and even in different parts of the same crystal. The
experience of diamond-cutters leads
Flickr
Stumbleupon
Scribd
