John Betts - Fine Minerals, dealer of fine minerals and specimens for mineral collectors.

Go To New Mineral Listings Added August 15

New Minerals are Added Every Tuesday at noon.

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See me next at:
April 20-23 2017, Rochester Mineralogical Symposium



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Guided Tour of the Mineral Galleries...

Mineral of the Week

Mineral of the Week
#68615, Pyrite with Chalcocite-Djurleite-Bornite coating, Milpillas Mine, Mexico (m) $65



News and Comments

Diamond testers are portable devices that test thermal conductivity of diamonds. Diamonds are composed of pure carbon atoms linked by double bonds, resulting in extraordinary thermal conductivity that distinguishes them from other gem materials. Diamond testers are used for testing faceted gemstones to confirm they are genuine diamonds.

Diamond testers have no use to test uncut diamonds (rough diamond crystals). That is because fake rough diamonds do not exist.

In the gem trade, fakers will insert faceted gemstones composed of lesser materials into parcels of diamonds to increase the weight of the parcel and raise the value of the parcel.

But the morphology (shape) of rough diamonds cannot be easily copied. And the value of rough diamond crystals is much less than faceted diamond gemstones. (This is the same reason currency counterfeiters fake $100 bills instead of $1 bills.) So fake rough diamonds do not exist.

It is true that "glassies", the planar octahedral diamond crystals can be faked. But why bother? And the complex diamond crystals offered for sale on this site cannot be faked.

If you are miner at Crater of Diamonds State Park in Arkansas, having a diamond tester is valuable for determining if the crystal you found is a genuine diamond. But the park service will test your finds and provide a certificate confirming it is genuine diamond.

But when buying from a dealer, that has tested the diamond before selling it, then a diamond tester is not required.

John H. Betts, 8/15/17

Click here to read past news and commentaries...



Customer Comments:

"Thanks, John. The sapphire just arrived in fine shape. Very nice and the color and clarity were well-represented by your photographs. Another satisfied customer!" D.D.

"An exceptionally beautiful fluorescent mineral expertly packaged and airmailed to me in perfect state. I am very thrilled with this purchase and plan many more." G. K. Tucker

"Service above and beyond! Recently I placed an order for a beautiful set of 10 Boleite crystals only to find that the set had been sold. Not to worry, John offered to custom build a new set of 10 Boleites which were equally (or even more) impressive as the first set. My Boleites traveled across the US and got to me within a few short days. I am extremely pleased with my set of crystals. The look is fabulous with an eye-pleasing mix of cubes and "twinning" crystals. Thank you for your exemplary service John!" M. Parrott

"We have, on several occasions, requested specimens that were not on your website. You have unfailingly come up with our requirements each time and they have all been top class :) We cannot thank you enough and look forward to dealing with you for a long time to come. Lots of thanks again :)" Marie

"For the better part of this past year I've been searching for just the right "raw and natural" diamond for inclusion to my mineral collection. After searching many sites I found just the right diamond with John Betts. It is a reference example of a perfect octahedral gem and in my opinion the finest example John had in the under 1 carat range.

My diamond is undamaged with no dark unsightly inclusions and is a cuttable gem-grade example. The service from John is exemplary and the shipping was extremely fast. I am pleased beyond 100%! My new diamond looks fabulous in my collection. John thoughtfully provided a circular - black cushioned display case with my order. Perfecto in every way. Now I will begin my happy dancing!!" Michael P.


Click here to see other comments about this site by customers. Also add your feedback...



Pledge to My Customers:

Customer satisfaction is my primary goal. I pledge:

  1. New minerals will be added to this site every week.
  2. All minerals offered will be naturally crystallized specimens - no fakes, no dyes,  no irradiation, no crystals glued on matrix.
  3. Only the exact item pictured on the site will be shipped - no substitutes.
  4. Photographs will accurately represent each item - no exaggeration, enhancement or retouching flaws.
  5. Mineral species and localities will be accurately listed on labels with each specimen.
  6. All items will be shipped via US Postal Service, usually the next business day after the order is finalized.
  7. Each mineral will be individually wrapped and carefully packaged to prevent damage during shipping.
  8. All historic labeling, if available, will be included with each mineral.
  9. Returns are gladly accepted. No questions asked, no explanation necessary.
  10. All customer information will be kept confidential and never shared or sold.
  11. I will continue to freely share my knowledge with others and contribute to the study and appreciation of minerals.
  12. All mineral specimens have a lifetime guarantee: if the mineral specimen is ever tested, and I incorrectly identified the mineral species, I will refund the cost of the original purchase & shipping, the cost return shipping, and the cost of the test.

 John H. Betts, owner
Mineral dealer since 1989, mineral collectors since 1967





Guided Tour of the Mineral Galleries...

(Minerals Sorted by Size)

(New Listings)




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Jump to the Home Page to see all sections of this web site Search this web site See the best minerals and diamonds available Visit the archive of over 75,000 mineral photographs Sign up for advance email notification when new minerals are posted Contact the owner via telephone or email Place an order for items on this web site

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New Listings1A

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New Listings2

New Listings3

New Listings4  

My Best Minerals

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This site has received the following awards:

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Surfing the Net with Kids 4 star site

This site was voted by as the most diverse mineral website on the Internet with, "richly varying mineralogy / geology content that is always fresh and up-to-date and perpetually useful to others."


John Betts - Fine Minerals, New York, NY
a division of, dealer of Fine Minerals and Natural Crystal Clusters since 1989.

Internet sales only - No showroom


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