The Opal 119
in
recent years has been the Australia mines, the most prominent being
White Cliffs, New gouth Wales. Extensive mining operations are carried
on there, the matrix of the opal being a cretaceous sandstone, which
has been permeated by hot volcanic waters. The output of this region
has already been represented by millions of dollars. Opals have been
obtained in commercial quantities at localities on the Barcoo River and
Bulla Creek, Queensland, and are occasionally found in West Australia.
The admiration of the ancients for the opal is expressed by Onomacritus, writing five hundred years b.c. who
remarks: " The delicate colour and tenderness of the opal remind me of
a loving and beautiful child." Pliny, whose voluminous books covered so
wide a range, and who evidently believed himself qualified to write
about anything, wrote of the opal: " It is made up of the glories of
the most precious gems, and to describe it is a matter of
inexpressible difficulty." The ancients esteemed the opal highly, and
attributed to it an influence for every possible good; this belief
outlasted the Middle Ages, and in the early part of the seventeenth
century the opal is recorded as being as highly valued as ever. Then
arose a
