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Dr Hanneman "The Jeweler's Eye"

I came across a Jeweler’s Eye , not sure about the operation of it. I was hoping someone has the instruction sheet and would be willing to email me a copy .
Thank you

There’s a book by Peter Read I think, called Gemmological Instruments that covers the Jeweler’s Eye. Dr. Hanneman was/is an amazing fellow. He talk a technique based on reflectivity in stones that you could use with your naked eye to identify gemstones. I watched him do that at Tucson one year, just informally. An amazingly well trained eye.
Google books has that book online. It might help you try out your Jeweler’s Eye.

Thank you, I’ll try to locate a copy.

You might not need to buy the book. Sometimes Google Books is awesome in this regard.

This Jeweler’s Eye is mentioned in two of Peter Read’s books, and here are links to those excerpts from each book.

(If these links do not open automatically, you might need to right click on a link to open it.)’s+eye+peter+read&source=bl&ots=KgwBxpHOUn&sig=HeXZGbXNhRbufFDhH2rWVDMJEak&hl=en&sa=X&ved=0ahUKEwjw9PnQr-PTAhVLxYMKHVSoAnAQ6AEIMTAD#v=onepage&q=jeweler’s%20eye%20peter%20read&f=false’s+eye+peter+read&source=bl&ots=hcQGD6ZsF9&sig=8mAtZjpGSecpJI9nok9PA0CYHEg&hl=en&sa=X&ved=0ahUKEwjw9PnQr-PTAhVLxYMKHVSoAnAQ6AEIKDAB#v=onepage&q=jeweler’s%20eye%20peter%20read&f=false

Thank you so much, the diagram pretty much answered my questions. It seems the LED lamp is not working. I would guess findind the part will be a challenge at least.
Thanks again.

Anyone who soley uses a “jewelers eye” which is a refractometer is asking for big troubles !!Many stones are not detectable via a refractometer or “jewelers eye” Dye, stabilization , borax filling or glass filling, etc etc cannot be detected . Many sapphire and ruby are infused, meaning they are dyed . In addition many synthetics like flux synthetic ruby and sapphire cannot be just tested by a refractometers. One must use a combination of tests and with flux synthetic sapphire and ruby one must use a microscope !!! Why?? ( from my days a owner and director Kingdom of Cambodia International Gems Pnohm Pehn Cambodia (95 % of ruby and sapphire in jewelers cases in Pnohm Pehn and even rough mined in P{a Lin is flux grown sapphire or ruby)
Flux sapphire and ruby is real . They regrow via melting down the junk ruby and sapphire and regrow it in a very short period of time versus real sapphire and ruby in the ground . One can only tell via microscope and a few other tests besides just a referactometer. The crystallization patterns of flux grown versus natural grown sapphire and ruby under 30x to 60x looks different between the two. A microscope is also used besides other testing to determine wether a green garnet is demantoid or grossular , etc Demantoid garnets show horsetail inclusions under 30x-60x microscope . Even emeralds such a chatham lab grown must be tested via other gem instruments and microscope to see the crystallization under 30-60X
Hydrothermal amethyst and citrine will need special testing versus just a refractometer since there is sop much hydrothermal in the market p[lace and why beads or cut stones in amethyst or citrine that is natural is far higher in prices then hydrothermal, quartz hoot with cobalt 50 /irridation to get citrine like colors, etc
Buyers must be aware and buy from legitament sources and use more then just a refractometer. On my trips to Africa i.e. Malawi , Zambia, Kenya , etc we met several supposed gem experts ( i.e. from India, USA, China, etc ) who bought supposedly super rough sapphire, ruby , aqua rough , color change garnets etc and all used solely a refractometer and were ripped off . Materials were flux synthetics-synthetics. Trust no one and test using often more then just one test !! In fact we have seen even errors in testing with GIA gemologists as well as with many African Minsitry of Mines labs as well. Synthetics, Glass, and Treated stones are all over even in Cambodia , Africa and Indonesia , etc Buyers must beware and use multi testing .
Lee Horowitz, M.Ed, CAGS, GemologistMiners-Cutters-Heat Treaters-carvers- Manufacturers Peru Blue Opal LtdHorowitz Co-Kingdom of Cambodia International Gemstone Co ltd (KCIG Co Ltd)Peru Blue Opal - Welcome

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Thanks for the great info. I do realize the extent one must test to identify gemstones these days but still found your reply informative. I was just trying to get the insturment back to it’s glory days and play with it a bit.
Thanks again for your responce.