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Describing unfamiliar stone


#1

WAS: Green Turquoise

How to describe a stone when you don’t know what it is?

I can identify a number of faceted/cabbed minerals by eye (agate,
jasper, moonstone, opal, garnet usually, etc), but sometimes just
can’t separate the natural from synthetics, or from some simulants
(natual vs synthetic aquamarine baguette, for example). I don’t have
access to a gemological kit either.

Depending on color, setting material and quality, and/or price vs
likelihood of the assumed identity, I can say with some certainty,
“It’s PROBABLY a synthetic whatever…”

I received a packet of closeout stones, marked as amethyst. Two of
them fairly screamed at me, “NOT amythest!” They are too brilliant
for their size and cut, and have a distinctive color change depending
on natural or incandescent or fluorescent lighting (different color
or mix in all three lights), and the colors were wrong for
alexandrite. After some research on various websites and books, I
concluded they were PROBABLY synthetic color-change corundum.

If real, they would be a pricey set of matched emerald-cut
stones…but considering the original price marked on them from the
original seller, it’s likely this is not natural material.

I have set them and want to sell them this year. Since I won’t be
able to afford a gemological kit until next year if I’m lucky, what
do I call such stones upon their sale? “'To the best of my knowledge,
these are very likely to probably be synthetic curundum. Maybe,
perhaps. And if they are natural, you have yourself one heck of a
deal.”

Or say you purchase some green-blue beads that the seller claims to
be turquoise; later you suspect they may not be as advertised. What
do you claim on the sales receipt?

I hope I don’t have to put aside half my gems because I bought them
before I knew they might be misrepresented…!

Thanks,
Kelley Dragon


#2
I have set them and want to sell them this year. Since I won't be
able to afford a gemological kit until next year 

Start by at least educating yourself to how to identify gems. The
GIA courses are probably too pricey for you if you can’t yet afford
any instruments, though I’d highly recommend them once you can afford
them. The installment payments aren’t so bad…

But if that’s too much, then at least get a good book or two on gem
identification. Liddicoats is the standard, but there are others,
and some might be more easily understood for a beginner at gem id.

And if you can’t afford proper gem identification equipment, you can
afford at least the basics.

A good corrected 10x triplet loupe. Don’t get a lesser type.

And a cheap penlight (the best are the really cheap ones using a
single incandescent bulb the front of which is a glass blob that acts
as a lens to focus the light. While these aren’t as nice for normal
penlight uses, compared to, say, a maglight penlight, the very
intense localized (at the bulb) light of those cheapies (cost a
dollar or three last I checked) makes them very useful for really
illuminating a gem (hold the front of that bulb right up to the side
of the stone while looking in the top. Anything within the gem lights
right up. With practice, almost as good as a microscope for seeing
inclusions…)

Then, even if you can’t afford a proper professional grade
polariscope, you can make one. Look for Hanneman (spelling? check the
archives) gemological equipment for cheap kits, or make one just from
a couple pieces of polarizing plastic and a bit of ingenuity. Even an
old pair of polaroid sunglasses will work. This does not have to cost
you lots of money to achieve basic functions of a polariscope. Won’t
be as nice as the pro versions, but it would let you determine single
refractive stones versus double refractive, and more easily see
pleochroic colors. This latter property, by the way, would easily
seperate your amethyst from possible synthetic alexandrite like
corundum.

A sensative scale would be good too. You kind of need one to sell
anything sold by the carat anyway, and once you know what something
weighs, you can use the measurements to derive what the stone should
weigh if it is a certain material with a given specific gravity. If
it weighs more or less than that, then you’ve a good idea what it
might be. The better the scale, the more accurate that guess. If it’s
really accurate, you can build a little apparatus pretty cheaply to
use it to directly measure specific gravity (at least for larger
stones, not so much melee.) That’s a pretty useful bit of data. Or,
again with Hanneman gemological equipment, you can build a little
home made but surprisingly accurate scale designed to directly read
specific gravity…

of course, what you really need for some of this, aside from
knowlege on how to use it all, is a good refractometer. Those,
unfortunately, aren’t so cheap. But again, with practice, you can
learn to visually estimate the general range of refractive index of a
facetted stone based on it’s appearance.

And the other option you may wish to explore is to make friends with
someone who DOES have the needed gemological equipment to tell you
what you’ve got. Perhaps a local lapidary club would find some hobby
gem cutter with the equipment, or perhaps a local jeweler would be
willing to take pity on you and help out. Worth looking.

But the bottom line regarding your stock of possibly incorrectly
identified stones is simple. If you don’t know what it is for sure,
then don’t describe it inaccurately. If you’ve got purple stones
that might or might not be amethyst, then sell them as purple stones,
not amethyst. If you don’t know whether the stones are natural,
treated, or synthetic or simply imitations, then don’t claim more
exact than you’ve got. If people ask (and they will), be
honest. Tell then you “THINK” the stone is such and such, but you’re
not sure, and it might be something else. If you’re honest, you
won’t get in trouble. Just be sure buyers really understand it when
there is some potential misidentification.

Peter Rowe


#3

If you purchased that packet of stones, you have a right to insist
that the seller identify them for you.

As far as the ones you have already set and intend to sell, it seems
to me to be imperative that you know for a certainty whether or not
they are genuine. You might want to consider taking them to a
gemologist, and having the stones evaluated as to whether or not they
are genuine.

At least then you would know for sure what they are, and can give
prospective customers a true statement as to whether or not they are
genuine, synthetic, or a simulant.

Alma


#4
I can identify a number of faceted/cabbed minerals by eye (agate,
jasper, moonstone, opal, garnet usually, etc), but sometimes just
can't separate the natural from synthetics, or from some simulants
(natual vs synthetic aquamarine baguette, for example). I don't
have access to a gemological kit either. 

John A. Roebling, designer of the Brooklyn bridge, had a saying: "It
is far more important to know what you don’t know, then what you do!"
And as a testimony of the wisdom of his saying, the Brooklyn bridge
still stands up to the modern traffic, while design specifications
called for horse carriages.

One of the most dangerous delusions in jewellery business is to
believe that gemstone can be identified just by looking at it. Even
more dangerous situation when such belief is combined with
availability of gemological equipment.

Recently I was called to appraise a 5 carat ruby. This story is a
real teachable moment. One guy was traveling in India and in one
small village he purchased a small lot of gemstones of blue, red, and
green color. When he returned, he showed the lot to his local
jeweler. I am not going to mention jeweler’s name or location. The
jeweler had a microscope and few other tools in his store. Upon
examination, the jeweler proclaimed that blue stones were lab-grown
sapphires; green stones were natural emeralds, but of very low
quality; red stones were garnets; and one 5.2 carat red stone was
natural ruby, which he offered to buy for 2500 dollars. I was asked
to give a second opinion.

When I examined the so called ruby, it was simply glass. The whole
lot was nothing but glass.

Leonid Surpin
www.studioarete.com


#5
later you suspect they may not be as advertised. What do you claim
on the sales receipt? 

This may sound harsh, its not meant to be, but…if you don’t know
what you are selling you should not sell them. Playing it safe and
calling them ‘unknown’ or you "might get a deal ’ works against you,
the client looks to you for expertise and isn’t getting it.

The flip side of this is why are you buying stones from untrusted
sources? My guess is you couldn’t resist the price. But now you’re
dubious and may not buy from that source again. Think how your
customer may feel buying from you.

For starting out you don’t need every gem gizmo in the book. Get
yourself a refractometer and polariscope first. With those two
instruments you can probably deal with 95% of the stones you’ll run
across.

As I recall you’ve recently set yourself up very nicely as a repair
shop, I guess you’re making some stuff too. You might look at it
this way…business investment and cashflow. To spend $1-2K up front
to test closeouts doesn’t make a lot of sense. In the interim, buy
from scrupulously honest sources. Sure you’ll pay a little more for
each purchase but you haven’t shelled out a pile of cash for
equipment. If you were to apportion just $10 for each time you test
you’d have to do 1-200 tests to make your money back. Of course
though you’re not really making money this way, its just a way of
judging the costs. Now think of how much money you could have made by
putting that 1-2K into more trusted stones during the time it takes
you to actually save up the cash for the instruments. You could
develop $6000 or more in income with that $2K if you put it in good
merchandise, “as needed”. So that 1-2K you spend on instruments too
early actually cost you 6K in lost revenue. Put your dollars where
they work.

I am not saying ‘do not buy’ the testing stuff at all. But you are
still in the critical first phase of start-up. Every dollar you spend
HAS TO serve your cash flow NOW. In some ways cashflow is more
critical than profit. Profit is the goal, cashflow are the plays that
get you down the field. You wanna score, you need good plays. Poor
cashflow can sink you faster than anything. Believe me on that single
point if no other.

Once you are firmly established you can make longer term
investments. That could be anywhere from 2-5 years.

If you’re doing appraisals, you will need some instruments asap
though or find someone nearby who’s willing to test for you.


#6

by the way, i have been seeing a lot of material, from thailand
especially ! being sold as paraiba blue tourmaline that is actually
appitite! anyone else seeing this??? be careful!! big difference
between a stone that can be as much as $7,000 per carat and a stone
that is $35.00 per carat!!


#7
you have a right to insist that the seller identify them for you. 

There are vendors of stones who don’t know what they are selling; and
some who do who won’t tell you accurately.

KPK


#8
by the way, i have been seeing a lot of material, from thailand
especially ! being sold as paraiba blue tourmaline that is
actually appitite! anyone else seeing this??? be careful!! big
difference between a stone that can be as much as $7,000 per carat
and a stone that is $35.00 per carat!! 

Big difference, too, in durability! Apatitie is really soft.

Marian


#9

Great advice from a jeweler friend, Jon Moriarity. When I was first
adding stones to my work and asked how I could know who to trust. He
said, anyone who tells you they can identify stones by eye is a liar
or a fool. I keep that in mind when I?m getting a feel for a dealer
new to me. Too full of themselves doesn’t sit well.

Marianne


#10

well I think parts of the discussion here on this thread has been the
reliability of the sellers, and the source of where one buys stones.
On one of the threads i started it was brought up you can’t always
know what you buy simply because of where you bought it at.


#11
Great advice from a jeweler friend, Jon Moriarity. When I was
first adding stones to my work and asked how I could know who to
trust. He said, anyone who tells you they can identify stones by
eye is a liar or a fool. I keep that in mind when I?m getting a
feel for a dealer new to me. Too full of themselves doesn't sit
well. 

If you are talking Faceted stones. I get you, but Cabochons? While
there are many that can’t be pinpointed to location, most can be
identified as to Species by eye.

And also, if you are talking about a dealer that has his or her own
inventory about their inventory, I would expect the dealer to know,
by eye, their own stock.

I do acknowledge the vast amount of lying that goes on in the gem
industry. I really don’t think, Marianne, your friend gave you a very
good maxim for dealing with dealers.

Besides that, it’s only a really small part of a large equation that
will not often even come up. And it would be hard to find that
context anyway.

There are vendors of stones who don't know what they are selling;
and some who do who won't tell you accurately. 

I have sold stones that i couldn’t identify. It’s cool as long as
they are sold as unidentified.

Also, adversely, a few years ago I purchased some large chunks of
Goshenite from a dealers Quartz bin while my wife bought Hiddenite
that came from a bin of Fluorite. That dealer also mixed massive
light blue topaz with massive aquamarine and sold it as aqua. Will I
go back? Heck yes!

If you want to know what dealers to trust, you do it like you would
any other friendship. You get to know them. You use your intuition,
because you really can’t afford to just trust everyone you’ve just
met.

BTW, the first piece of jewelry I ever bought was a 3 carat ruby
ring set in sterling silver for $24. This was from a roving vendor at
a community college during the time the grants payed out. I said “is
this really a ruby? For twenty-four bucks?” He said “Yes it is”. “Are
you sure it’s not a garnet?” “No, it’s a Ruby”. It was 1982. That
year it was stolen.

I know, in hindsight, that that stone was a garnet. And I am
visually making that identification based on a 27 year old memory. :slight_smile:

TL Goodwin
Lapidary/Metalsmith
http://thepacifikimage.com


#12
I do acknowledge the vast amount of lying that goes on in the gem
industry. I really don't think, Marianne, your friend gave you a
very good maxim for dealing with dealers. 

My experience is that some dealers, rather than lying, just don’t
know how to identify gem material and can’t tell the difference
between glass and quartz beads, aqua and blue topaz, ect. People buy
gems for resale and trust the person they buy from. If it was sold
as ruby and they don’t know the difference between a garnet and a
ruby, and it is a garnet, it is usually ignorance. There are vendors
from overseas that are given material and sent over here by family or
acquaintances and these people sometimes have no clue as to what
they are selling, they just go by what they are told.

Usually when I tell a dealer what they are calling something when it
is something different, they do care and re-label the item. One of
the most common misrepresentations is gems that look like blue topaz,
garnet, and peridot beads or faceted gems, they contain spherical
bubbles, so they actually are glass.

Since we all experience other peoples behavior differently, I am not
sure what it means “Too full of themselves doesn’t sit well.” If
someone has something I want at a good price, their attitude does not
deter me as long as they do not abuse or insult me. I am not going to
marry them.

Over 30 years of being aware of the gem market, I have learned that
when something is available, it might be quite transitory and the
mine can be depleted quite quickly.

The gem business is actually quite a small number of dealers that
are the sources for the majority of gem materials. All the other
dealers buy from them and resell. If you go early to a show, if you
pay attention, you might see the dealer you buy from making a
purchase of what you buy from him from another dealer. There are a
few dealers who have fine quality goods, turquoise or tanzanite, more
people selling medium quality, and many more selling low quality. I
attend the Denver Gem and Mineral Show every year as I live in Denver
and rarely do I see misrepresentation of gems. There are hundreds of
dealers, and quite a few have been attending for many years and have
good reputations. It is usually people selling beads and carvings,
serpentine “jade” or something like that.

There are a lot of man made azurite, lapis, turq, and sugilite beads
and rough blocks for sale. These materials are not labeled. The
tricky part would be, if you buy this material not knowing it is
created, technically there is only misrepresentation if you ask if it
is natural and you are told it is. There is supposed to be
disclosure, but there is no enforcement.

I have bought turquoise rough that showed no sign of treatment, I
was told it was untreated, and it smelled like plastic when cutting
it. It was bought from a tailgater in a parking lot. FTC regulations
don’t mean anything when the dealer you are buying from is back in
China or India when the show ends. When vendors come to my store,
very rarely has anyone not been knowledgeable about what they are
selling. Usually it was someone who bought gems overseas and got
what they paid for, but not anything any jeweler I know would buy as
they overpaid or bought poorly cut gems.

Richard Hart G.G.
Denver, Co. 80210


#13
by the way, i have been seeing a lot of material, from thailand
especially ! being sold as paraiba blue tourmaline that is actually
appitite! anyone else seeing this??? be careful!! big difference
between a stone that can be as much as $7,000 per carat and a stone
that is $35.00 per carat!! 

In 90’ when prices on Paraiba started to increase, we use to buy a
hundreds of melees everyday, and to avoid the Apatite mixed in, I
started to use a density liquid. Wasn’t 100% safe method, but it
helps me a lot to make easier a latter selection.

From Brasil,
Vlad Radu Poenaru


#14

Richard,

There are a lot of man made azurite, lapis, turq, and sugilite
beads and rough blocks for sale. 

I couldn’t help but notice that there was a lot of “sugilite” at the
recent Denver show. It didn’t look right to me as it was light purple
with a white matrix. I didn’t bother inquiring on price because I
sensed a fake or another mineral being sold as sugilite, perhaps
stichtite. Did anyone else that went to the Denver show notice the
sugilite?

I’m sure there will be some at Tucson next year.

Rick Copeland
Silversmith and Lapidary Artisan
rockymountainwonders.com