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I don't know what kind of stone this is, it looks like sapphire but the hardness is not right

With the banding, I’d say it’s a Kyanite

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Kyanite is probably not sir… when light passes through it, you can see the blue-violet clouds with a bit of gold inside it. and under the light it is purple black

how did you do a hardnest test??? if you do a Refractive index test and specific gravity test then you should know ???

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I am not a Gemologist, I’m a gem cutter, and there is a sequence that is followed when trying to identify a gem or rough. Colour is to some respect irrelevant except to exclude material that is not know to exhibit a specific colour.

As a gem cutter I need to confirm the material I am about to cut, so the first test I do is a Specific Gravity test, it is simple and will quickly provide a narrow realm of possible materials and eliminate one hell of a lot. Only after completing an SG test do I explore hardness. Hardness testing does ideally require a testing set, I don’t have one and have never needed one, between a variety of known rough materials I usually have something that will point me in the right direction. Likewise streak tests really only work with materials falling into a narrow range of SGs.

So if you wish to identify this gem or any other you are trying to identify, learn how to do an SG test, it is simple and all you need to buy is a good set of scales, everything else you probably have floating around the house.

If it’s softer than Sapphire, it might even be glass… who knows, but do an SG test first and tell us the results.

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thank you, a very good tutorial for newbie like me, thank you very much

the specific gravity of the stone is 4.75 .thank you


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That would indicate the stone could be Zircon, it is also softer that Sapphire at Moh 6-7.5. If is Zircon it is darker than what I am familiar with, and it lacks any brilliance which Zircon is known for due to its high refractive index, this could be due to poor cutting. From here you would need more detailed testing to confirm the stone’s identity.

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Are you sure about the SG? Namely, do you get the correct SG for known gems? The reason I ask is that it looks like iolite, but iolite has a much lower SG.

serendibite I think it is. it has a perfect resemblance

Have you done an RI?? That will help narrow it down further.

Maybe it’s Spinel which has a Hardness of 7.5–8.0 and SG as high as 4.40, otherwise it averages from 3.58 to 3.61.
It really is next to impossible to verify a mineral’s ID over the internet and via photos only. For all I know, considering the last photo shows a white line up the middle, it could have been man-made via Hydrothermal means (starting with a seed plate). And if that’s the case, it could be anything from Quartz to … ??
Take it to a Gemologist (Jeweler ?) to have it tested.