Hi What are these and what are they used for?
Thank you
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Hi Louis,
Welcome to the forum!
You have an interesting image there! It looks like some green crystalline-like material, but without more context, it is impossible to identify them.
A couple of things you can do to help us, help you:
- Take some images of one or two of these with some close up views and use a sheet of white paper as the background. Take a couple of images of each side, including the ends.
- If you can measure the weight and measure the dimensions of these, we can possibly start narrowing down the material.
- Do the shorter dimensions look like a hexagon (six sides), a trapezoid (five sides), a square, or round? (It is difficult to see this in the image.)
Do you know where they came from?
Cheers!
Thank you for the questions and suggestions I will be adding more detailed photos.
They are round and not large in size. From what I was told they are from Brazil.
Thanks again more to follow.
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Hi i would suggest typical tourmaline crystals thanks
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They are most likely going to be tourmaline. However, without further information nothing can be said for sure.
-Daniel
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could be tourmaline or beryl from the prismatic and what seems to be hexagonal shape… However close ups and physical data such as specific gravity, hardness, refraction would be helpful… can’t do anything but guess with the current image… almost everything comes from Brazil, so that’s not too helpful either.
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Louis,
Thank you! The size reference of the dime is very helpful. As is the hexagonal shape cross-section. @SydP’s suggestion of these possibly being tourmaline may have some traction.
@StevenH26783’s suggestion for the refractive index measurement would be the best diagnostic test to do. Unfortunately, the Specific Gravity range of tourmaline is quite large. A polariscopic test might help but can be difficult with some varieties of tourmaline.
A few articles on the material:
https://gemologyproject.com/wiki/index.php?title=Tourmaline
If you do not currently have access to instruments like a microgram/carat weight scale, refractometer, polariscope, etc. The hardness test Steven suggested and a streak test could be used, but they are destructive in nature.
The one behavior tourmaline exhibits that is uncommon with most gemstones is it a pyromineral. This means when heated, it produces an electrical charge bias. This can be replicated without using heat, because the mineral is also triboelectric. Where you can use a fabric cloth like wool, nylon, and even paper to rub the stone in a single direction which will generate a biased electrical charge on its surface.
Using ground black pepper on a piece of paper, and after rubbing the stone with a material mentioned above, bringing the stone near the pepper grains, may induce them to be attracted to or repelled from the stone.
A fun experiment, but does not really provide a good identification test.
It would be best to take a few of these to a local gemologist at a jewelry store or appraisal company to see if they can identify them for you.
Cheers!
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the closeups and dime do help a lot… the crystals are very small, possibly beryl by hexagonal and prismatic habit, but much more likely to be tourmaline…
your suggestion of the triboelectric effect should very helpful…quartz is strongly negative but I think that it can be ruled out… great suggestion!.. nonetheless, taking the stones to an experienced jeweler or gemologist is still better yet.
basic triboelectric series for heavy minerals
The Journal of The Southern African Institute of Mining and Metallurgy VOLUME 110 REFEREED PAPER FEBRUARY 2010 77 â–˛
Table II
Apparent triboelectric series for selected minerals based on inductive separation
Mineral name Recovery Charge acquired Comment
difference (%) (apparent)
Apatite -70.0 +++++++ Strong positive
Carbonates -40.2 ++++ Moderate positive
Monazite -38.4 ++++ Moderate positive
Titanomagnetite 0.4 . Neutral
Ilmenite 0.8 . Neutral
Rutile 2.0 . Neutral
Leucoxene 2.4 . Neutral
Magnetite/haematite 3.2 . Neutral
Spinels 3.4 . Neutral
Garnet 5.1 . Neutral
Staurolite 6.6 . Neutral
Altered ilmenite 13.3 - V. weak negative
Goethite 14.4 - V. weak negative
Zircon 20.4 – Weak negative
Epidote 20.9 – Weak negative
Tremolite 21.3 – Weak negative
Hydrous silicates 22.5 – Weak negative
Aluminosilicates 23.6 – Weak negative
Tourmaline 24.8 – Weak negative
Actinolite 26.0 – Weak negative
Pyroxene 29.7 — Weak negative
Titanite 39.1 ---- Moderate negative
Feldspar 43.0 ---- Moderate negative
Quartz 66.8 ------- Strong negative
None of the other minerals on the list are likely candidates…
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Hi My Name is Emanuel I think you Might have apatite crystals it strongly resembles Tourmaline in colour especially Paraiba tourmaline for Neon blue green colour plus its crystal system is also Hexagonal, Tourmaline is trigonal so they are Uniaxial crystals, thisI hope helps,
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Wow a lot of great information Thank you all. One more question please.
How or what can they be used for?
Thanks again
Hi Louis,
These are fairly small crystals. Faceting them can be done, but the resulting stones would be baguette or melee sized. May not be worth the time and costs.
In their natural state (as is), they can be mounted in jewelry pieces as complementary stones for a larger central pendant, brooch, or earrings. Someone with good wire-wrapping skills can make some simple mounts and articles with these.
-Troy
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Thank you Troy
agree with TroyJ… the crystals are really too small to facet. unless you are an expert gem cutter, sending them out to be faceted wouldn’t be cost effective. setting them as is, either wire wrapped, set with prongs, capped on one end with a small loop to dangle in a necklace could be a jewerly alternative. Since they are so small, many stones or all of them in a single piece would be attractive and unique. ID’ing the stones are the first step.
It’s aquamarine. Used for? Bits of fashion jewelry.