Search the Community
Showing results for tags 'calcite vein?'.
Found 1 result
Hi everyone, A friend recently found this exposed on some fault breccia that outcrops between a Lower Carboniferous fluviatile sandstone and volcanic neck composed of basalt in my hometown. My friend is convinced the main constituent of the breccia is sandstone but when it is broken into it is full of amygdales containing calcite crystals, and is not made up of grains. His main reason for thinking it is sandstone is the light color, most but not all igneous rocks in this part of Scotland are quite dark, however Ive found basalt containing agates that is almost cream in color nearby. He is also convinced that the object in question is a permineralized tree trunk showing cell structure, while I think it is calcite growth of some kind that has formed along a slichenside. I cant think that Ive ever heard of permineralized plants showing cell structure being preserved in sandstone, I'd be interested to know if anyone else has? Can anyone help put this debate to bed? Any help much appreciated! Best regards Sam