Lime Green Minerals (Found in CT in beryl mines)

These were recovered from a beryl mine in the middlesex county area of Connecticut. (Portland or East Hampton)

They are lime green in color

I dont know if they are part of the beryl, but I would think not because the beryl recovered was either golden or more emerald in color.

Hardness?

Might be shards of chrysoberyl, but need to know the hardness as Stephanie requested.

Good luck and welcome to the forum.

Regards george

They look like Peridot to me

Amanda

Stephanie Martin Wrote:
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> Hardness?


I dont know much about hardness, but I did a little research on the hardness scale and checked to see if it could scratch quartz(7), and it could not, I tested it on a piece of green calcite(3), and it did scratch it. Then I tested it on Fluorite(4), and it also scratched it.

did you collect them? if so, PM me exactly where from and I can tell you what they might be.

-Rowan Lytle

Necessities:
Food, Water, Shelter, Fire, Minerals.

They look a lot like the peridot you find in the San Carlos basalts in Arizona.

Daniel, you may want to do a mineral search on Mindat to see if any of these potential minerals occur in Connecticut and if any are near you.

I tried searching at the specific mines that I went to, but there are very few pictures uploaded. Ill do a little more research

The hardness test you did rules out chrysoberyl (which is confirmed found in Connecticut) and any mineral that is harder than quartz. Without a good crystal termination or cross section it is difficult to determine. An SG test would be useful in this situation. Perhaps even a streak test? Hopefully Rowan will be able to nail it for you.

regards,
stephanie

It really does look like peridot to me.... however. There are no such occurrences of peridot in connecticut. Perhaps I am the first? I do have a good eye

I thought Peridot also, ut purely from color which isn't very reliable. You need more data points. Try a pen knife (hardness 5.5) and a steel file (7) to get a better idea. Peridot is around 7.

John Stolz Wrote:
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> I thought Peridot also, ut purely from color which
> isn't very reliable. You need more data points.
> Try a pen knife (hardness 5.5) and a steel file
> (7) to get a better idea. Peridot is around 7.

Hmmmm. Since you said that I tested it on pyrite (6.5 - 7) and the mineral couldnt scratch the pyrite cube or quartz.

the pyrite couldnt scratch the mineral back... BUT quartz did leave a faint mark.

I retested it on Fluorite(4) and the mineral DID scratch the fluorite(4).

So the hardness must be between 6-7...



Edited 1 time(s). Last edit at 06/11/2012 05:00AM by Daniel jacobs.

The occurrence of peridot in a felsic pegmatite seems unlikely to me however I agree that the proposed identity of this mineral seems fairly accurate. Be careful, as it may very well be a specimen with a foreign origin that was disposed of at the collecting site. This situation is commonly encountered and can make things quite confusing both mineralogically and geologically!

Beryl, in between green and golden would be my guess based on the (typically inexact) hardness tests and color. I agree with Jeremy, a beryl-bearing pegmatite is a highly unlikely environment for peridot.