applied
to the variety in which the patches of color are small, angular,
variously tinted, but evenly distributed. Common opal, so-called,
exhibits no play of color. This variety is found of many hues, chiefly,
however, milky, rose-colored (when it is called quinzite), and green.
Hyalite,
Muller's glass, is the name applied to a colorless, transparent,
jelly-like variety, usually occurring in botryoidal masses. Moss opal
is the name applied when the variety contains dendritic marking;
semi-opal when impure ; opal agate and opal j'asper when a mixture of
either agate and opal or j'asper and opal; opalized wood, when
replacing wood; and hydrophane when it is transparent, or exhibits play
of colors on being wet.
The
noble opals of Honduras are often exceedingly beautiful, although not
as fine or as durable as those from Hungary, which are the finest in
the world, and the most valuable. The Honduras mines are little worked,
and the opals only seldom reach the market and generally in an uncut
state. A remarkable specimen of these weighed over a pound, and when
cut furnished a quantity of fine stones, some of the finest of which
are in the collection of Dr. A. C. Hamlin.
The
best description of the Honduras deposits is that given by Dr. John L.
LeConte, of Philadelphia, Pa,, who, in a report which he made on his
return, says : " Extensive beds of common opal and semi-opal are seen
along the belts extending through the central part of the Department of
Gracias. The localities worthy of exploration are those in which the
opal forms veins,, not beds, in compact but brittle trachyte of a dark
color. The veins, as will be seen, are not confined to such rocks, but
seem to have their origin in it, and probably are not found except in
connection with it. The best known mines of precious opal are in the
Department of Gracias; several localities have yielded valuable gems,
but they are all remote from the line of road. Some are in the vicinity
of the town of Gracias, others near In-tibucat; but the most important
ones are at Erandique. The working is now carried on in a very small
way, but the locality is extensive, and in the opinion of Dr. LeConte,
mining on a large scale would be attended with profit.
The country near by abounds with common opal, but the
