#Labradorite Feldspar
3 messages in this thread
Does anyone know where Labradorite can be found as well as what ranking it has
as a gem. We have inharited a large amount of uncut raw materiel which we would
like to find out the value.
david 74534,1514
Hi, David–
Welcome to the forum/section! The Lapidary Journal of Aug 93 has an article
on gem feldspars – your town library may have back issues.
60% of earth's crust is feldspars, a group of which labradorite is a member. It
is quite common, but only rarely does it take on gem quality. Thus its value
may be anything from zero to significant, depending on color, visual texture,
and freedom from flaws. Many labradorites are accounted gems because they show
a schiller called labradorescence; the prize among these is Finnish
"spectrolite", a variety of labradorite. "Madagascar labradorite" is
technically andesine, a very similar feldspar showing this schiller. Oregon
sunstone is another form of labradorite showing "aventurescence", a glitter
caused by large numbers of tiny flat metallic inclusions. A lesser kind of
sunstone is found at many other locations – this is technically oligoclase, yet
another feldspar. But these feldspars are easily confused, and yours may not
be technically labaradorite, even though someone calls it that – these minerals
shade into one another and are very hard to distinguish, and it is not critical
to gem value anyway. What counts is color, luster, etc.
Not being a lapidary, I could not guess on prices. If anyone here knows
enough, they will surely need to know something about the color, the visual
texture (labradorescence, aventurescence, etc.), transparency, etc. Telling us
where it is from, if you can, may help.
–Doug
David,
One book I have lists occurrances in Italy, Finland, USSR, Greenland, Canada
(on the Labrador Peninsula), California, and South Dakota. I also know that it
has been reported in upstate NY. It's usefulness as a gem will depend on many
factors, mostly play of color. It's not a highly valuable material, but
popular for cabs. I have one current listing for $3.75 per pound.
Are you thinking of selling some of it? I'd be interested in small quantities
at a reasonable price. If so, send me a CIS-mail message.
Al