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[adshah]

Hello to all ,

we have found a couple of almandine depost , But the extracted stuff are all non gemmy , how could we know whether inside gemmy garnets may consists or not.

We would highly welcome and appreciate for your suggestions

regards

ads

[neoman789]

Put it to a bright like and look at the edges

[neoman789]

I have a nice 30 0z one in my collection and it looks opaque but in the light its transparent along the edges so im sure its gem quality

[Jason]

Smack them with a hammer..i assume you want to know if they are gemmy inside because you plan to extract or sell the gemmy portions(if they have any) and/or cut any gem rough on the inside? Gotta get it out one way or another and a hammer is just as good as anything...I sat on my driveway smaking alamandines one time..all North Carolina specimens(all junkie ones mind you..wouldn't smack a nice large dodecahedron)..needless to say..no gem rough..sigh

[Tracy]

Hi adshah -

Your question isn't clear to me. Are you asking how to tell whether non gemmy-looking almandines have gemmy material inside them, or how to tell whether there are gemmy almandines present inside a deposit which so far has given you non-gemmy garnets. Could you please clarify?

- Tracy

[adshah]

Hello Tracy ,
Thanks. And you are right . How to tell whether there are gemmy almandines present inside deposit.

[adshah]

Hello ,

Many thanks for two of our friends Amethystguy and Neoman 789 for providing suggestions .

[Peter Megaw]

Frequently the kind of metamorphism that makes these will have "focus" zones where the conditions were a little better for gem formation, so you should look around for them...follow the deposit laterally to see if the quality improves up down or sideways. Weathering may also have affected the crystals near surface,...especially if you have a freeze-thaw cycle where water can get in along cracks and shatter the crystals when it freezes. Fundamentally, the only way to tell if there are gemmy ones deeper is to dig deeper...just try to dig where the stuff you CAN see looks best.

You might want to construct a screening device to aid this effort. The best one I have seen is a glass cylinder (a tall jar) with an elongate light behind it (actually a "portrait lamp" available all over in lengths from 10 to 30 cm with a nice metal housing). You put two strips of opaque tape along the length of the cylinder, separated by about 1 cm to create a linear light strip and block extraneous light. Fill the cylinder with water, which reduces the refractive index contrast significantly...you can use glycerine or something with a slightly elevated RI, but water is really good enough. Then you use tweezers (or your fingers if the cylinder is large enough or your hands are small enough...to hold the garnet or other rough piece in the water behind the strip...giving you a very focused view of the piece and the ability to identify gemmy zones. I have also seen a dry version used for preliminary screening before getting wet....this was just a 1 cm square hole in an opaque plate with a light behind it.

You can adjust the width of the light strip by moving the tape and/or blocking it down to a smaller "window" for more precise viewing.

[John S. White]

Without revealing the exact location of your deposit, can you tell us approximately where it is and what type of rock the crystal occur in? The vast majority of almandines found in metamorphic rocks have little, if any, gem potential.

[adshah]

Hello respected Peter Megaw and John S. White .

I am very glad to receive your suggestons and ideas . In comming april / May I will post garnets on matrix found in great himalaya area Nepal .

Thanks

shah