88 A Book of Precious Stones
Montana in the United States, but the products are not of commercial importance.
Corundum
rubies formed of ruby material by artificial methods have attracted
attention and are cutting some figure in the jewelry trade, but they
are not and can never be the peers of natural rubies; man's ingenuity
and science cannot compete with Nature in the gem business. Artificial
rubies are described in another chapter.
Of
the other stones than corundum called " ruby," the only important ones
are the varieties of spinel, which chemically is closely allied to
corundum so that the red varieties of spinel might be regarded as
cousins-german to the real ruby. The " Cape ruby"—so called in the
jewelry trade—is pyrope garnet from the diamond-bearing rock of South
Africa, and is described in its proper place—the chapter on the garnet.
Stones sometimes substituted for the ruby by dealers, or mistakenly
called rubies, are red tourmaline, or rubellite, called " Siberian
ruby"; rose topaz, called " Brazilian ruby "; and hyacinth or jacinth,
which is zircon, and is described in the chapter on " Semi-Precious
Stones Occasionally Used." Spinel has perhaps a wider range of colour
than almost any other mineral,
