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Hydrogrossular Garnet?

I got a white ‘Hydrogrossular Garnet’ today from Afghanistan, via Pakistan. Only place with real info on them is Gemstone Magnetism
They mention green and pink versions fluorescing under 405nm laser light, but not the white ones. As you can see, it fluoresces.
Not tried SW or LW uv yet. Other than it’s not so strong under LW uv.

Focus is out a little bit, but you get the idea.
Anyone know anything about these stones, its possible it’s a white Grossular one, but looks too milky to me.
I’ve not had time to do any RI or SG tests yet, I only got it this morning, and the fluorescence surprised me, so I thought I’d pop up on here and see what happens, if anyone knows anything about them.
I will post what i find with the tests at a later date.

It’s 17.11cts 17.4x12.4x8.4mm approx

Ha! I just noticed the top picture looks like a grey scale copy of the bottom one, it isn’t, honest.

There are LEDs that illuminate in the purple range, which includes 405nm. Have you tried them? You could use several at once to get enough brightness. LEDs are a lot cheaper than lasers and very simple to wire up. Might be worth a try…

I’m looking at those now, and I should of taken the 405nm picture in a dark room, but i didn’t, i stayed where I was with the same light source on (sun) that I used to take the first picture, and it still lit up well. I’ll have to try a dark room and use the other uv sources I have to see if they do anything or not.
Just seems odd that a light fequency above uv can get them to fluoresce.

I have a transparent Apple green which is VS1 and though they tell you the gem is never transparent this gem is. It is about 4 carats and was bought from my friend at Ravenstein Investment Gems years ago. It has been lab tested twice and both report transparent untreated Hydrogrossular garnet. It is on our website www.oldvirginiagem.com