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Gemological instruments

Dear all

I am planning to start out in Gemological studies and wondered if
any of you would have some tips on buying RELEVANT instruments. I am
on a budget and will use the instruments in my jewellery-studio for
study and stone id only. No need, at present, to impress customers
with fancy benchtop models.

Must have’s?
What to look for?

Thanks for your help.


Check this out.

Dr. Hanneman is not afraid to point out that most gemmological
instruments can be made or purchased without the expense that Gem
Instruments will try to incur on you.

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I suggest a good refractometer (not the cheap ones you see on e-bay)
and a digital weighingscale so you can build your own hydrostatic
balance. A loupe is a primary instrument that you should have in your
pocket at all times.

If you are on a budget, a microscope will not be on your christmas

Other nice things to have (and affortable) are a dichroscope, and a
chelsea filter. You can build your own polariscope with a flashlight
and some polaroid lenses (break down that '70s pair of sunglasses or
buy some at the local photoshop).


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    I am planning to start out in Gemological studies and wondered
if any of you would have some tips on buying RELEVANT instruments.
I am on a budget 

You’ll need a good gemological refractometer to measure refractive
index (RI), but good luck finding one on a budget. Fair deals can
sometimes be found on eBay, but buying a used one sight-unseen that
has a scratched hemicylinder will just make you cry. A new GIA
refractometer lists for around $660 US. There are less expensive
refractometers out there that are not bad for flat facet readings,
but they don’t work as well for spot reading cabochons. If you don’t
know what that means, trust me - you will, eventually. RI
measurement is arguably the most important clue in gem ID, as is
birefringence. I suggest you buy the best one you can afford.

A good gemological microscope with darkfield illumination is another
necessity. It would be nice to have a zoom model, but I’ve gotten by
with an inexpensive GemOro 10X, 30X quite nicely. I’d trade a lot
for a nice 10X - 64X zoom, though. Many get through GIA’a Gem
Identification program with a 10X loupe, but you’ll do much better
with a microscope. You can find the GemOro all over eBay for around
$300 US

A polariscope is a must, also. Fortunately, you can get by with a
couple of polarizing lenses from a cheap pair of sunglasses and a
light source. You’ll need one to determine optic character, etc.

A calcite dichroscope also comes in handy, as does a Chelsea filter.

An accurate gem scale to determine specific gravity. A lot of people
use SG liquids for this, or both, as I do. Also, there are balance
scales specifically geared to measure SG. SG is a valuable clue for
gem ID, nearly as valuable as RI.

Also consider a Longwave/Shortwave UV light. They can help make a
lot of separations.

There are plenty of other things you will eventually want, but this
is the short list of what I consider to be absolutely necessary to
begin the study of gemology. Once again, I’d recommend getting in
touch with:

Hanneman Gemological Instruments
PO Box 1944
Granbury, TX 76048

Available there are inexpensive SG liquids, microscopes, the famous
SG balance scale, loupes, dichroscopes, spectroscopes, some very
useful gem filters, etc. However, I do not recommend the RR
Refractometer. While it may be a useful indicator of a gem’s nature,
it isn’t sufficient for serious beginning gem ID study, in my

Also, go to Ganoksin’s Jeweler’s Selected Bibliography and search
"gem identification." The URL: Every book on the
page is worth purchasing.

One of my favorite web sites has an intro page for aspiring
gemologists with an open offer to download any of the info for
personal study. To the left of the page are studies of most of the
equipment I’ve listed above. Check it out:

Best of luck to you in your studies,

James in SoFl

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For basic info try:

as well as my articles at the Ganoksin Project.


Charles Lewton-Brain/Brain Press
Box 1624, Ste M, Calgary, Alberta, T2P 2L7, Canada
Tel: 403-263-3955 Fax: 403-283-9053 Email: @Charles_Lewton-Brai1

Question out there for who might have a answer. GIA course vs GIA Diamond and Grading is A few bucks more than DCA’s for $ 125 or $175 for 22 LESSONS, online print version vs GIA $1,670 on-line for 20 lessons .

Finished the Prerequisite and Currently taking the GIA Diamonds and Grading class (online). And I just came crosses this post and surprised about what i read on: about the other organization.