This looks like calcite, but bright green, any ideas what it is? :confused:

🔗Capelcleugh-Lead-Mine-User-Album-Image-30483[linkphoto]Capelcleugh-Lead-Mine-User-Album-Image-30483[/linkphoto][/link]

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Could be copper stained Aragonite?
Mike

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could still be calcite with a bit of cu staining,

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Do you know if the mine in question is a copper or lead mine?

If copper.... more likely to be copper leaching out from the hydrothermal veins seeping out of the cracks of the country.

The blue could be Allophane, which if my memory serves me correct is a hydrous aluminium silicate. This can be found in many copper mines, especially where arsenopyrite and clay fillings can be found.

I'm not too sure without looking up on the mineralisation of lead mines what it could be if the mine in question is a lead one.

A number of what is termed "secondaries" appears from copper and lead mines. This happens when the mineralisation mixes with or runs into other mineral veins and copper/lead secondaries appear. There are many websites available to have a look at that will give you more information than I have here. I'm not a mineralologist.

It was in Caplecleugh, which is lead. There are a few other minerals down there, but not sure what :confused:

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That is almost a nickel green. Traces of nickel are widespread in the Nenthead mines, as proven by mineral collectors. Nickel can substitute for zinc in hydrozincite, and hydrozincite is abundant as a major component of the snow-white coatings that form where there is sphalerite. When hydrozincite picks up a few % of nickel it turns green. Of course one cannot be sure from a photograph. One would have to actually collect a sample and chemically analyse it to be sure.

if you look at the pics of Cammock eals mine there is one which has got some blue staining on it, its on the slitt vein which has small amounts of chalcopyrite in it, some of this may have leached out, and thats an ex lead mine ex fluorite mine, so it could be anywhere in the dales in any of the mines, as it is in the Yorkshire Dales mines.....like gold its where you find it.

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Looks like melanterite to me (hydrous ferrous sulphate) formed from the oxidation of pyrite. Easy to tell just taste it - if its very metallic and smells of rusty metal there is your answer.


These are a couple of photos of Melanterite in a crystalline form in the Lece Mine in Serbia. The green colour is from the iron content NOT copper or nickel.

[photo]Personal-Album-1490-Image-30660[/photo]

[photo]Personal-Album-1490-Image-30661[/photo]

Not sure about the correct designation, but calcite looks in the right ballpark. As you also get malachite formed from carbonic acid (limestone), if there is limestone, there will probably be calcite! and it follows trace malachite.

There are all sorts of varieties of allophane/chrysocolla with colour "dopings".

(See the comprehensive answers on "what's the blue stuff?" thread

I gather metal salts are apt to taste "astringent" and I gather that tasting the water was employed in lots of Cornish mines (probably elsewhere too) as an indicator of soluble salts. I think copper sulphate is particularly definitive.

It's odd how elfnsafety have moved modern chemists away from using their senses to quantitatively analyse "stuff". The nose is indespensable in organic chemistry. I gather taste was pretty good in the inorganic/mineral stuff. A smell is quicker than whacking it in a machine. Usually more portable also!

Lots of it is quite toxic though!