Name that scunge...

[Cantclimbtom]

Blue/white crystalline growth that I believe formed by seepage not an actual ore -- not certain!. Iron mine, Cretaceous sandstone above a harder grey limestone with a thin band of silicous poor iron stone/clay between. Blue/white scunge is roughly in area of the clay, so any damp would be from clay or sandstone above. Last worked 1857

Blue looks copper to me, but the only thing that matches pictures is copper hydroxide like Spertiniite, but this isn't a rare ore from Kazakhstan it's "scunge" in an English mine.

Any good suggestions anyone? Am I missing the obvious somewhere?

 

[Cantclimbtom]

Scale of pic is about 1foot by 1foot to box in the scunge. Didn't notice any other sign of copper or sulphur anywhere else while down there

 

[AR]

Iron phosphate can be pale blue in some hydration states, AFAIK - the most common mineral form (Vivianite) is green but might be worth having a look on Mindat for iron phosphate minerals?

 

[Cantclimbtom]

Thanks!!! Seems most plausible  :bow:
https://www.mindat.org/min-4194.html

There's zero evidence of copper or sulphur but there is iron, albeit in obvious uneconomic quantities (some people must have lost a tidy sum of money on that mine). Minedat description seems to match very well. Without testing, after reading that... I'm pretty confident it's that

Thanks again