My boys will be selling used Raman Spectrometers. These units are mil spec, hand held, and can run analysis software either on an (Android) phone or a (Windows) laptop. Connection is via WiFi. Analysis software uses the RRUFF database. I believe they want $5k for them. There will be several with them at the Tucson show, so let them know if you are interested.
I should mention that a Galaxy 6 (at least) should be used for the phone - it takes about 12 seconds then to identify the stone from the spectra (mostly loading the database). My much older phone (a Galaxy 4, I think) took 3-4 minutes to load the database. I suppose with a laptop with an SSD it would be much faster. The software was designed to work with this spectrometer, but should work fine with most other spectrometers for gem identification.
Yup - after a little bit of searching, I find it is partially diamond coated CZ (they use something else as well to help the diamonds stick as I understand it). If you look up diamond coated CZ Raman signatures, you will find a large number of spectra which don't look at all like this -- and this one from the company that makes them.
Joined: Sun Oct 16, 2005 12:22 pm Posts: 21602 Location: San Francisco
Curious. The diamond spectrum offered has nothing to indicate Type IIA....I guess they used their own knowledge of what they were testing. Tempted to get a 4mm stone for $32 and see what kind of results I get.
Joined: Sun Oct 16, 2005 12:22 pm Posts: 21602 Location: San Francisco
Hi Dr. Hanneman. Normally sound advice. BUT this stone is a fake-up. CZ with a diamond coating....diamond coating is atoms in thickness usually. Normally when these simulants are tested with sophisticated spectrographic instruments, the diamond doesn't show up at all.
David/Stephen: Can you post a pic of the stone? Have you tested it on pavilion facets? Does it exhibit an orange flash?
Oh wow. this website is great....".... Therefore dirt, grime, hand oils, lotion, etc will stick less to the Asha because of the diamond coating, and your stone will remain much cleaner than an ordinary CZ."
Thats because diamonds dont like grease and oil...grease table sorting must work by magic I suppose.
Sorry for the thread hijack. 5k on a Raman seems pretty awesome really. Asha diamonds....not so much.
_________________ Professional Gemologist and Microscopist
The views expressed here are the author's opinions and do not necessarily reflect those of the his employer.
With the exception of Raman spectroscopy, standard analytical methods and instruments used in major gemological laboratories are unlikely to detect a very thin, colorless, carbon-containing coating on a polished CZ or other gem material—or, if such a coating is detected, to confirm that the carbon is in the crystalline form of diamond. Raman spectroscopy is the most established method for determining the type of carbon present in a material.
The diamond Raman peak (produced by sp3bonding of carbon atoms) is located at 1332 cm–1, while the graphite-related Raman feature (where the carbon has sp2 bonding) is a broad band centered at ~1550 cm–1 (see Zaitsev, 2001, pp. 69–70,111–112). Our Raman spectroscopy investigation was unable to detect the 1332 cm–1 or the ~1550 cm–1 peak even with a 325 nm UV laser at liquid- nitrogen temperatures on the CZ plate represented as having a “thick” coating.
For fun, Team Challener, can you super impose the spectrum for CZ on top of your spectrum for Diamond and Asha? Thanks.
Hi, perfectly matched cubic zirconia spectrum - http://www.ramansystems.com/english/gem ... alysis.htm For cubic zirconia spectrum could be different due to doping, most probably formation around 1300 cm-1 is PL of rare earth element doping as the stabilizer. P
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