On Tue, 31 Mar 2009 20:22:36 -0700, in rec.crafts.jewelry robynahawk
Post by robynahawkGeorge - I think you have a Jeweler that actually knows her stuff!
http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness
One thing to keep in mind about mohs hardenss is that it's simply an order, not
a good linear scale. Diamond, at 10, is some 40 times harder than sapphire at
9, depending on how you measure it. And sapphire is harder than beryl by more
than the interval between quartz and topaz. Also, hardness is only the measure
of how easily the stone can be scratched. It is not the same as toughness, or
the resistance to chipping and breaking. Spinel, for example, is a bit softer
than sapphire, but it's a good deal tougher and harder to chip. One can
illustrate the difference with a piece of glass, and a piece of plastic like
nylon. A sharp corner on the glass easily scratches the softer nylon. But drop
them both on the floor, and the plastic bounces while the glass shatters.
Topaz, as you note, is harder than quartz. But it's not as tough, what with a
perfect cleavage direction.
Post by robynahawkWhen looking for a stone that you want to wear daily - this should be
your FIRST resource.
Kunzite is a 6.5 - so too soft for everyday wear. If you knock on
something it tends to get small feathery fractures inside the stone.
When it was introduced (by Tiffany's) it was referred to as the
"Evening Stone" as it shouldn't be exposed to sun for extended
periods - the color has a tendency to fade.
Not just a tendancy. It WILL fade, though how fast depends on the intensity of
the light and the duration. Also, like topaz, it too has a direction of perfect
cleavage (this is a direction through some types of crytals along which it's
much easier to split the crystal.)
Post by robynahawkQuartz (Amethyst) is a 7 - and while it would hold up to frequent wear
- it can get scratched up - but then too it is fairly inexpensive and
could be replaced when the stone starts to show wear.
Topaz is an 8 - the only Topaz that will show wear is the Vapor
Deposition Treated "Mystic" varieties as it is a surface treatment.
Again - cheap enough to replace.
Some is cheap. In the pinkish tones, you can get into the so-called "imperial"
topaz, which depending on quality and size, can get at least into the hundreds
of dollars per karat. Still likely within the budget, but I don't think I'd
call them all exactly cheap. Also, though they are an 8 in hardness, their
slight brittleness and that cleavage direction does make them vulnerable to
chipping and breakage, even if they don't get too scratched up.
Post by robynahawkInteresting she didn't mention the Beryl Family - also an 8 but more
of them are natural colors so less chance of getting that worn look -
maybe she just doesn't have any Morganite (more of a peachy pink).
Good call. I forgot that one too. Morganites aren't as common as some, nor are
they a bright pink, but they are indeed pretty, and so long as you stay out of
top quality aquamarines, or any decent quality of emerald, they can be
affordable. Personally, I like the golden beryls better. Bright clean lively
golden colors, and not excessively priced.
Post by robynahawkAs the previous posters have mentioned Spinel is an excellent option -
but I have to disagree with Peter - I don't think that Alexandrite is
in your price range. However - since you were considering a
synthetic stone in Moissanite you may want to look at the Russian Lab
Grown Alexandrite - you can get the showy size you are looking for
with the added bonus of "color change"!
I didn't imply that natural alexandrite was in the price range. I said they're
costly. I might have added that in the finest qualities, they can be among the
most costly gems you'll find around, if indeed you can even locate a stone in
those rare qualities. You can find moderatly priced ones on the net, but
frankly, most of them are somewhat less than stunning in appearance. And I'm
being tactful with that characterization.... :-) However, as you note, you CAN
find good and attractive synthetic alexandrite. The russian ones are nice, as
you mention. Personally, I also quite like the Chatham ones. as well. Maybe
it's just that "made in the U.S." thing right now... But Tom Chatham is a neat
guy, and no doubt appreciates the business.
Post by robynahawkOther inexpensive and showy looks might be a Malaya Garnet - pinky
purple - or a Rubellite Tourmaline!
Go to your bookstore - get a copy of Gemstones of the World by Walter
Schumann (short sweet and easy to read) - and do some research!
Another good call. There are also many good sites on the net with decent
gemological info for free. Be a bit wary of any who are coupling it with a
strong attempt to sell you gems, but nevertheless, there's a lot of good
gemological info on the net. Wikipedia has a goodly amount, for example.
Peter