COLOURED DIAMONDS. 61
disfigures the majority of the stones, especially the larger, brought from Brazil. Barest of all was the Black, until the recent discovery of the Carbonado, whence
now may be cut any number of this contradiction to the very idea of the
Diamond ; concentrated darkness in place of light.
The most charming piece of jewelry that I ever beheld, was a spray composed with exquisite taste entirely out of coloured Diamonds
of all the tints that could be collected in ten years' research by the
artist-goldsmith (one of the true Cellini breed), its ill-remunerated
deviser.
The
most complete collection of coloured Diamonds ever formed was that of
Virgil von Helmreicher's, a Tyrolese who had spent much of his life in
their pursuit in Brazil. After his death they were secured for the
Museum of Vienna.
This
distinction of colour was noticed early. Ben Mansur founds his minute
system of classification upon it, placing them in the following
descending order of value :—1. The White, transparent. 2. The Pharaonic (without
explanation). 3. The Olive ; or white passing into yellow. 4. The Eed.
5. The Green. 6. The Blue. 7. The Fire-coloured. "The two first are the
most plentiful ; the others are rare : hut the rarest of all are those
quite polished (naturally) : " meaning by the last the Naifes of the Hindoos.
ARTIFICIAL IMPROVEMENT OF THE DIAMOND.
Large
stones, besides flaws and specks of different colours, sometimes
inclose cavities filled up with a black sediment that discolours their
whole mass. How to get rid of such impurities without excision and the
necessary destruction of the magnitude of the diamond is the problem
that certain chemists profess to have solved. De Boot positively
asserts that his imperial master, Eudolf II., had
