Photography Showcase 3 per week limit

[The Old Ruminator]

The Last Sandwich.

 

[JonP]

A midweek trip beyond the first gate in Bagshawe Cavern. Here, quietly off to one side is the epic blasted out dig through a humongous calcite boulder choke which Keith 'Ben' Bentham aptly named 'England's Green and Pleasant Land' Maybe someone who was around at the time could provide context to it's naming? Maybe the first photo has something to do with it?


Jim Climbing through the blasted choke in England's Green and Pleasant Land by Jon Pemberton, on Flickr


Jim climbing the boulder slope to reach Father Time by Jon Pemberton, on Flickr

 

[Pegasus]

Triangles - National Speleological Society https://share.google/2MUYoc0m47Gq2OCs0

It would seem to be a rare habit of calcite. I have seen better images on t'web but of course can't find them now! Apparently it forms underwater, or at the surface. This may explain its friable nature?
Of course I am not guaranteeing anything and would like to know other ideas

That's a fab link, thank you

 

[The Old Ruminator]

In The Crystal Garden . Jonathan's Chamber, Withyhill.

 

[Brains]

Interesting to see the triangle habit of the calcite crystals
@pwhole a clearer example of something like what you found?

 

[pwhole]

Indeed! That is really interesting. I sent the link of my photos to geologist Noel Worley, and he replied:

The macro images are fluorite 'epimorphs'. These are the product of fluorite crystalising as an external cast over either, a rock or another mineral. In the example in question, the original material has subsequently dissolved away leaving a cast in fluorite of its original form. There are some clues about the original rock or mineral. The complete dissolution suggests the original was calcite or limestone. I have a specimen collected from Treak with original calcite/limestone still intact that has been partially replaced by fluorite.

 

[The Old Ruminator]

And One Became Three, Withyhill,

 

[shotlighter]

And One Became Three, Withyhill,

I like the little chap in the centre, looking back at the camera. Though I think he stood there too long.

 

[The Old Ruminator]

Great Balls of Fire.

 

[pwhole]

Synchronicity

 

[bagpuss]

Supra Avelines Shaft, Burrington Combe @Dingley Dell