knew nothing of the Western continent, says: "India is the
sole parent of the opal, thus completing her glory as being the
great producer of the most costly gems," but he admits that
either a variety of this species, or one closely allied to it,
denominated " lovely youth," was brought from Egypt, Arabia,
and some other regions of the East.
The principal varieties are the precious or noble opal, common opal, fire-opal, jasper-opal, wood-opal, girasol, cachelong,
hyalite, hydrophane, asteria, and a kind exhibiting dendritic
markings, sometimes called moss-opal. When the colors are
broken into small masses, it passes under the name of harlequinopal ; and when characterized by an orange hue, it is golden opal.
The noble or precious opal, giving out different colored rays
in bewildering succession, constitutes one of the most beautiful
ornamental stones in existence, and has always been regarded
as one of the most desirable and attractive for personal use.
When employed in jewelry, it is cut with convex surfaces, en
cabochon, on both sides. Carnei are sometimes carved on this
gem, in a manner to present the figure on a ground consisting
of the dark brown matrix.
The fire-opal, found in Mexico, Hungary, and the Faroe
Islands, is characterized by its remarkable flame-like reflections
of hyacinthine red, passing to honey-yellow, and sometimes
presenting all the prismatic colors. The two largest fireopals known in England, according to Streeter, were found in
the Hungarian mines in 1866, and exhibited at the Paris
Exposition of 1867. They are drop or pear-shaped, one of the
gems weighing one hundred and eighty-six carats, and the
other one hundred and sixty.
The variety known as hydrophane was so named from its
peculiar property of becoming transparent when plunged into
■water. In its ordinary state it is white or reddish yellow,