Klerksdorp Spheres are small, spherical or disc-shaped objects found in three billion year old pyrophyllite deposits in South Africa. They look manufactured, but they formed naturally in volcanic sediment.
earthstory reblogged
earthstory reblogged
theveggeologist
Spent some time photographing a quarry here in NC for my 3D modeling thesis project. This quarry is no longer active as they have moved to a new site nearby, but it was quarried for pyrophyllite, a phyllosilicate mineral that is very similar in property to talc. Since it has been raining these rocks literally crumble with a small bit of pressure which is pretty fun if you want to feel like you can crush rocks with your bare hands, but it makes for climbing around to mark things difficult.
I have found some really great specimens of pyrophyllite that show the amazing crystal form it has. These are some pics I took, the second one with a macro lens.