Cave in Baryte Vein ?

The Old Ruminator

Well-known member
I was looking at a cave recently that was formed partially in a pink vein in the limestone. I picked up this sample with green intrusions and wondered if that was copper. Indeed is the vein baryte ?



Baryte limstone interface. Pretty stuff and similiar to samples for sale on ebay.

 

Brains

Well-known member
The green does look like malachite, a copper bearing mineral.
Where was this found? Most baryte I have seen from the UK is more creamy and less crystalline.
Does the piece feel exceptionally heavy for its size compared to limestone? That is a major diagnostic (baryte is very dense, "heavy")
Very hard to tell from just a picture, but gut reaction leans towards dolomite, or a dirty calcite - stained in the matrix.
Doesnt mean it isnt baryte tho'
 

Brains

Well-known member
The Old Ruminator said:
Its quite heavy. I dont want to pass on information re the cave as yet as its unexplored.

Fair enough, assuming UK it is very well crystalline and a good sample. The weight will be the main thing for an easy ID, compare to similar size bits of limestone, or even concrete, if it is VERY heavy then probably Baryte
 

pwhole

Well-known member
I found a good piece of pink baryte in a pipe working underground last year - it has yellow coxcombs interspersed, and clear/cloudy crystals of some other mineral scattered even more sparsely, but I have no idea what they are. It's very heavy indeed, and is about 10cm X 7cm X 5cm. The odd thing is it's the only piece I've seen in there - none in the walls, on the floor, anywhere - just this one piece buried in floor-sand. Last week I found another piece of vein mineral that has a similar waxy/soapy surface to it, as the piece pictured above, and some of it is certainly baryte, but there seems to be another greyish crystalline mineral I don't recognise. I'll try photographing it close-up to see if it's any more revealing.
 

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Subpopulus Hibernia

Active member
Probably malachite. I've retrieved samples from a barite mine in Ireland that has similar (though less dramatic) green flecks which are identified as malachite in the technical literature on the mine. There are also yellow and black flecks which are ores for iron and lead - though I forget the names of those minerals. 
 

AR

Well-known member
If you can flake out some of the green bits, drop them in dilute acid - if they fizz and the acid turns green, it's malachite. If it does nothing, then it's probably pyromorphite but there are some other possibilities like vivianite or glauconite.

I've got some samples of barytes from Crich that look similar apart from the fact they're brick red!
 
AR said:
If you can flake out some of the green bits, drop them in dilute acid - if they fizz and the acid turns green, it's malachite.

A demonstration we often do at Alderley Edge open days is to put a small bit of malachite into distilled/white vinegar. It then goes a nice blue colour and if you then put a clean piece of iron in, a small quantity of copper metal will form on the surface.
 

The Old Ruminator

Well-known member
Not Tankard Shaft but a cave where access has not been negotiated with the landowner. We are working on it and if we get a positive result I will post it up on the forum. Its a surprisingly big cave. I would rather the location was not referred to at the moment.
 

Duncan S

New member
rhychydwr1 said:
Is this cave Tankard Shaft Dig?  Found some similar Barytes there.
We'd love to find a sample like that!
But our miners seem to have done rather a thorough job of taking out every last scrap of mineral and we still don't know what was being mined.
 
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