ARTIFICIAL DIAMONDS
M. Moissan describes the method of procedure in making microscopical diamonds as follows : —
A small charcoal crucible is filled with broken bits of iron and carbon of sugar, placed in a furnace wherein a heat of 40000 to 50000
C. is generated by two electrodes connected with a powerful generator.
When thoroughly heated, the crucible is removed from the furnace and
plunged into water. This process is similar to that demonstrated by Sir
William Crookes (see page 139). M. Moissan relates that the removing of
the diamond from the centre of the solid iron is a delicate task which
takes nearly three weeks. " That I have obtained diamonds there is no
doubt, but they can be seen only by the aid of the microscope."
It
has recently been contended by Mr. George Friedel that high temperature
is an essential condition to the formation of the diamond. He is also
of the opinion that the greatest importance should be given to the
quick cooling of the iron containing the carbon. His experiment
consisted of placing two electric carbons as shown in the sketch; one
was solid, the other had a hole through the centre. A strong electric
current was passed through the carbons, forming an arc at A. A
piece of iron wire was fed slowly through the hollow carbon and was
melted into globules, which fell into a dish containing quicksilver and
water. Upon dissolving these globules the residuum was examined under a
microscope and found to contain infinitesimally small crystals which
were determined to be diamonds.