LABRADORITE AND OTHER GEMS. 329
The green carbonate of copper receives the name malachite \
the blue carbonate, that of azurite. There is only a slight
difference between these two species except in color — the constituents being the same, with a little variation in their relative
proportion. The azurite presents different shades of azure —
blue to a deep blue ; that found at Chessy, France, has been
denominated Chessy-copper, or chessylite. The bright green
malachite is spotted and banded with tints of paler green ;
it is very soft, having only a hardness of three and one-half,
but on account of its remarkable play of colors and capacity
for polish, when found in masses of sufficient size, it yields an
excellent material for ornamental vases, boxes, tables, and
other articles of similar use.
These minerals are the native products of many different
countries, but the Russian mines yield the best quality of malachite, especially those of Prince Demidoff, in Siberia, whose fine
collection, exhibited at the Exposition of 1851, first directed
public attention to this material for decorative purposes.
Though it is developed in many of the states and territories
of this country, and sometimes in considerable masses, it has
not yet been mined for art uses. A rare specimen of malachite and azurite combined, discovered in Arizona, was seen
at the New Orleans Exposition.
The mineral collection of St. Petersburg is said to comprise
one specimen weighing ninety pounds. A remarkably beautiful vase of malachite, made by order of the Emperor Nicholas
for the King of Prussia, is in the Museum of Berlin ; and
another magnificent vase, presented by the same royal donor to
Sir Roderick Murchison, the celebrated Scotch geologist, is
contained in the Geological Museum of London. Ancient
engravings on malachite are seldom met with, though one
specimen of the kind is said to be found among the Pulsky
collection of gems.
