What else is in this matrix with Emerald Beryl??

I went mining recently in Bordonaro Mine, Portland, CT and I dont know what the tan colored matrix is called.

This appears to be Emerald Beryl, Smokey Quartz, and Mica. Any ideas on the tan colored mineral?

Based on the form/appearance, associated minerals, and location my guess would be stained albite/cleavelandite.

regards,
stephanie

Forgot to mention about a hardness of 5-6

Albite would come in around 6 - 61/2 so it is close. I'm sure the Connecticut experts will chime in soon enough.

regards,
stephanie

A typical pegmatite mineralisation. Beryl, black mica (Biotite) and Smokey Quartz are clear to see. The tan mineral is Microcline, i think. In Austria we have very similar occurences. The greenish Beryl is a common Beryl, i suppose. Only if Chromium/Vanadium are the reason for the color it is Emerald. In more than 90 % of pegmatites it is common green Beryl, not Emerald.

It certaily looks like one of the feldspars?

Spencer.

How much is the color an artifact of the photograph? The first photo does not seem as tan as the other two. Given the locality, I tend to agree with Stephanie and would go with the clevelandite variety of albite.

Feldspar

The tan colored mineral is brittle. I was enhancing my specimens by chipping off some of the tan mineral with a screwdriver and a dull knife. But it was able to scratch fluorite

Albite/Cleavelandite and Microcline are all Feldspar group minerals. Sometimes they are both present in the same sample and sometimes you may not be able to determine 100% which type. Therefore you may just need to leave it at Feldspar.

And Gerhard is right about the common green beryl versus emerald.

regards,
stephanie



Edited 1 time(s). Last edit at 06/16/2012 07:23PM by Stephanie Martin.

Wow! Apparently I need to do more research. I thought I was collecting emerald and aquamarine beryl. Im confused... because if you look into portland connecticut, there are pictures of aquamarine beryl that were collected from those exact locations that look just like mine. Here are some more that I collected from portland.

In my opinion...
pic 1- Aquamarine Beryl
Pic 2-Heliodor Beryl
pic 3-aquamarine beryl and heliodor

This is important to me because I recently opened a collectables website, and correctly naming these minerals is crucial.

Im doing some research... and Im finding that there is only (EMERALD, AQUAMARINE, HELIODOR, MORGANITE, GOSHENITE) beryl forms.

So what is green common beryl? Wouldnt it be emerald or aquamarine? Please enlighten me

Daniel, it is all beryl. Emerald is really, I believe, a gemological term applied to essentially transparent, bright green beryl where the green is due to the presence of chromium (and sometimes vanadium). I am not sure what the chromophore is in aquamarine, but the color is blue or blue-green. Morganite is pink beryl. Goshenite is colorless beryl. And heliodore is yellow beryl. But, they are all varieties and in the final analysis they are all beryl.

Okay. It is very difficult to find alot of information on beryl. I might take it over to a mineral specialist or a local gem store. I am only concerned on this topic because I will be selling my specimens, so I wouldnt want to sell one for 10$ when it might be worth 100$ or vice versa.

Daniel,

The problem you have found is that these names "emerald", "heliodor", and "aquamarine" have different usage by different people. In gemmological circles, these names are exclusively reserved for material that can be used for gems. That doesn't mean that they have to be 100% gemmy, but it does mean they have to have some aesthetic value when cut and polished. Sadly, most of yours wouldn't make that grade.

However, in mineral collecting circles, these names are frequently used to refer to green/yellow/bluish beryl crystals regardless of gem quality, so your use of these names is no more incorrect than other people here who are using them - but at the same time the people who say these are NOT emerald, etc, are also not wrong.

Personally, I wouldn't use these names to describe your crystals, and "beryl" is a much better name in general.

Ah, thanks for the clarification. It might be the safest bet to name them all as Beryl to avoid any problems. Im guessing price directly related to the quality (no fractures), size, and hexagonal form of the beryl as well. I might have to check out the "sold items" of beryl on eBay to get a good reference. Thanks for all your help guys. You really know your stuff. The info you guys give is much more useful than looking online on official websites.

Daniel,

You might find it useful to read the beryl articles in the "Best Mineral" section here at mindat. This link will take you to the main beryl article which contains links to articles on the different varieties of beryl.

Olav