Dear Ive,
Sorry to have gotten under your skin. The disdain you sensed in my
posting was directed at the writer of the glossary site not at you.
Nevertheless, let me respond to the points you raise.
First, about apache tears and obsidian, the glossary makes the
following just plain false statements: Under the heading mahogany
obsidian it says, “Mahogany Obsidian (also called Apache tears)” and
under the heading of obsidian it says “Obsidian (also called Apache
tears).”
As for the glossary’s definition of apache tears, it reads, “Apache
tears (a type of obsidian) is a volcanic glass that is usually black,
but is occasionally red, brown, gray, green (rare), dark with
’snowflakes’ or even clear.” While it is true that apache tears is a
type of obsidian, it is not true that it occurs in such a variety of
colors and patterns; the definition actually applies to obsidian, not
apache tears.
Here’s the email I sent on 12/24 to the site’s contact address:
“Apache Tears are not also known as obsidian nor vice versa. Apache
Tears are just one type of obsidian, usually black or brown and shaped
like small pebbles (hence “tears”). Some other types are rainbow
obsidian, sheen obsidian, and velvet peacock obsidian, in addition to
the mahogany and snowflake obsidians you mention. One explanation for
the name Apache Tears is that it refers to the hardships suffered by
the Apache tribes during the European conquest of the Americas.”
On the other hand, the moonstone issue is not so cut and dried.
Even the three sources I consulted (Frederick Pough’s “Peterson Field
Guides: Rocks and Minerals,” “Simon & Schuster’s Guide to Gems and
Precious Stones” and “Simon & Schuster’s Guide to Rocks and Minerals”)
don’t agree on much except that moonstone, whatever variety, is
feldspar. But let’s look at the main points of the glossary’s
definition anyway.
First it says, “Moonstone (orthoclase) is made of albite and
orthoclase feldspar.” Well, if moonstone is orthoclase, then it can’t
be “made of albite” which isn’t orthoclase, but rather one of the
plagioclase feldspars. Also, moonstone may be albite and may be
adularia (an orthoclase feldspar) but it can’t be both at the same
time.
Next it says, “Adularia is a common type of moonstone.” � True
Then, “Oligoclase is another type of moonstone.” My sources mention
oligoclase in connection with sunstone; if it’s also a type of
moonstone, I can’t find the reference.
And, finally, “Labradorite and albite are rare forms.” As far as I
can tell, albite isn’t rare at all and labradorite isn’t moonstone at
all. Labradorite is frequently sold as “rainbow moonstone” but,
according to G.I.A., there is no such thing. “Rainbow moonstone” is
merely a trade name, used because it’s a lot nicer sounding than
labradorite. (Then again, “moonstone” is really just a trade name,
too, isn’t it, so maybe the whole argument is moot!)
I’ll grant you this, my dear Ive, my eye did slip over the word
albite in the site’s definition of moonstone, but that doesn’t make
the definition nor the site itself any more accurate.
Beth