please start with basic tests… if you are going to collect stones, you will need to know how to do them and what equipment is necessary… doing SG reading is very simple… suggest that you google it and read several sources… better than someone trying to write a long essay about it…then try it out at home for yourself.not complicated or difficult at all… other basic tests include refraction… refractometers are worth the investment, as they are less than $200…also Moh’s hardness… not suitable for all stone, but the edge on your speciment can be scratched against references in a kit to determine hardness.
Pictures can’t substitute for testing, but in conjunction with testing, a far more educated guess can be made…as is, could easily be blue cobalt glass…
Suggestion of sending it for LA ICP MS not economically feasible without narrowing it down to something truly valuable…
ICPMS prices are negotiable depending on what information you want and where you go. A quick scan for identification is coming down in price. However, the killer is cost for sample preparation and also having a representative sample if you have lots of samples. The chosen sample needs to be free of cracks and major inclusions unless you want multiple scans that cost extra money. Also, it needs to be small and usually encased in epoxy and polished so that you get a good laser spot or spots to work from. Nothing at the moment beats this identification technique, Clearly, it won’t give you a valuation on a stone, and there is always the question of whether the information gained is worth the expense. However, I’ve found that no other technique compares, such as in my present research into Mud Tank zircons.
Best of wishes on your research…
Would very much want to read your paper in prepublication.
I’m in Chicago for the annual Goldshmidt meeting of the international and european geochemical society… am an associate member of the American Geophysical Union… Not a professional geologist, just an interested amateur who evolved from a rock collector into a scientific paper collector… I have open access to C cubed, Geophysics, Geochemistry and Geosystems… all of the papers are open access…
Since you are doing research and not selling gems professionally (are you doing both?) using LA ICP MS is the only way to go… unless you are an academic or grad student, doing research at an academic institution, paying for multiple samples is too expensive… about 10 years ago, I was interested in doing whole rock analysis for basanites, nephelinites and other undersaturated rocks from the Honolulu Volcanic series. prices quotes were 2K per sample… need a dozen or more samples for comparative geochemistry, with several from the same source…prior papers had well outlined eNd, trace element profile… wanted to focus on certain trace element isotopes, in very small concentration… below Ni, Ti, Ba, etc and light element isotopic composition for mantle xenoliths in peridotitite and garnet eclogite… would have gotten professional help from University of Hawaii geology department… but it was cost prohibitive. Plus being an amateur and not professonial, would end up being second or third author…
X-ray diffraction is another techniq
there are numerous methods to test at a higher level of precision than home tests and tests done with the usual gemologic equipment that are only good for screening unless provenance is already know.
Hand held XRF machines cost 12-50K depending on X ray flux and sensitivity… these machines can detect trace elements but are poor at detecting light elements including silica, Mg, O, Na.
Lab XRF machines are much more expensive but more accurate. Hand held machines are for field work. EMPA or electron microprobe analysis is even more sensitive and accurate… uses high voltage electrons to excite inner orbital electrons and records X ray spectra, rather than X rays to excite them as in XRF… EMPA can focus on micron sized mineral grain within a thin section. CT scanning can be done on small fragments of rock… Scanning electron microscopy can identify nanosized particles within a rock but not their precise chemical composition… Petrology starts with thin section optical analysis to determine the modal composition of rock. The technique is tedious… AI may supplant human observers but it still is done by undergraduates and grad students to determine mode as a learning experience… crossed polarizing filters are used to determine angle of extinction and identify individual crystal grains…the areal estimate of the minerals present in a field determines the mode. Other techniques using mass spect are sensitive enough to almost count individual atoms. LA ICP MS and SIMS mass spect are the gold standard and the only way to separate out isotopes, as well as to determine elemental abundance. Isotopes partition between core, mantle, and atmosphere…lighter isotopes are in general more mobile and will separate out from heavier isotopes… All of these techniques require expensive machinery… the cost of LA ICP MS is 500 to 1.5M USD, SIMS cost up to 6 milllion… annual operation costs are 50 to100K… all of these expensive or more expensive than a medical high field (3T versus 1.5T) commercial MRI machine. Operating costs for an MRI easily exceed 100K per year, not only in supplies of liquid helium, gadolinium contrast, maintenance, but also technician salaries which are high…However, MRI machines make a good profit… petrological analysis doesn’t…
agree 100%
I vote with the others that this is glass. Don’t need expensive equipment or testing as discussed futhur up on this thread… simple RI, SG will distinquish glass from a gem mineral. These tests are home tests and not 100% accurate… if your reading come back as a gem mineral, then the next step is expert opinion…professional jewelers and gemologists have more sensitive equipment plus, most importantly, experiene.
Another consideration … Cobalt (or just blue) spinels could come natural from Afghanistan and have a very similar color. They are also a very popular synthetic, but real and synthetic are gorgeous when cut.
Hi there. Given the provenance of the stone, and if you’re lucky, it might turn out to be afghanite. Does it glow orange under uv light?
Hi, I am a newbie and no expert on anything but that looks like an exceptionally good piece of blue amber from Indonesia.
Whatever it is, it is a very nice color but TESTING is the only way you are ever going to know what it is. At the very least we need the Hardness and the Specific Gravity, both of which are easy to determine (a youtube video would show you how).
Actually, being from Afghanistan, I wonder if it couldn’t be a really high grade Spodumene or maybe even a Spinel ?
It looks like it’s sitting on a Camera Shutter. Having something beside it for scale might be helpful too. You are welcome to MAIL it to me and I’ll test it for you 