the moss-agate from Colorado; or on beaches, as the agate, chlorastro lite and thomsonsite from Lake Superior.
Nearly
all the gems found in these ways are sent to the large cities in small
parcels, or are sold at the localities to tourists, or are sent to
other localities to be sold as having been found in the vicinity. Many
of the gems are known only locally, some to mineralogists only, and
others that are mentioned here are known only to a certain few who
constitute the gem collectors of the United States, and whose one
object is to find something that possesses the qualities of a gem or
precious stone, for the purpose of enriching their cabinets ; still a
list of this kind will be of interest and value to ti e mineralogist
and to many others who may have never known of their existence in this
country, to whom this knowledge may have a commercial value, should
some of these minerals be met with in sufficient quantities and of good
quality; it may also direct attention to what has a value and has not
heretofore been utilized. Wherever a gem is mentioned from the sale of
which a small amount has been realized, it is mentioned merely to note
its occurrence in this country, whereas in other countries the gem is
often found of better quality and in larger quantities. A list is added
of the principal gems that have not been found in this country. and
also a list of those that have not been found elsewhere.
We
know that the mound builders have worked the turquois mines of New
Mexico, that they have made arrow and spear points of rock crystal,
smoky quartz, and obsidian, and that they have buried crystals of
quartz with their dead; that the fluorite of Hardin county, Illinois,
was by them worked into ornaments, and that some of the most beautiful
agatized and opalized woods, agates, jaspers, and obsidian were by them
worked into arrow-points, and now after a long time are mounted as
ornaments by the white man, the precious stones thus serving a double
purpose.
Diamonds.—Diamonds
have been occasionally found at a number of localities in the United
States, but as yet at no place has more than an occasional crystal
occurred, never enough to warrant any extended mining for them. The
diamond found at Manchester, opposite Richmond, Virginia, weighing
after it was cut over 10 karats, is worthy of mention. An occasional
stone has also been found at the Portis mine, North Carolina, Hall
county, Georgia, (a) and with platinum in Oregon. They are also
reported from Idaho, San Juan county, Colorado, and from Cherokee Flat
and several other localities in Butte county, California. A beautiful
crystal that cut a remarkably fine three-eighths karat stone wasfound
near San Francisco. Two crystals weighing over2 karats each are on
exhibition at a jeweler's in Indianapolis, and are said to have been
found in Indiana. Within the past year a diamond is reported to have
been found in Missouri by a hunter who was stopping to take a drink of
water at a small brook. This diamond weighs 2-1/2 karats, and by some
a American Journal of Science, II., ii., 253, and xv., 373.
