PYRITE BALL - USA

Description

ITEM #2353
This pyrite specimen formed in a layer of shale, in southwest Marion County, Indiana.  The shale in which this specimen occurred is named New Albany Shale, which is part of the Borden Group (Mississippian Age), 359 to 318 million years ago. When the shale was in the form of mud eons ago, it is believed some organic material (a twig, a bug, snail, leaf, etc.) got trapped in the mud.  While the mud was soft, the decaying material drew in iron and sulfur to combine into iron sulfide, the formula for pyrite.  Pyrite in the shape of a ball is uncommon but can be found in other locations around the world.  This location produces some of the best pyrite balls found in the world!
This specimen is in the shape of a sphere. It probably formed from some round organic material  such as a bug.  The crystals are very bright and shiny and range from small to 3/8 inch.  The crystals are mostly modified cubes with some octahedral points, and they have a nice pyrite luster. The larger crystals are on opposite sides of the sphere with tiny sparkly pyrite crystal in between.    Nice specimen !
The specimen is 1 1/8 to 1 1/4 inches in diameter.  It weighs 2.25 ounces (64g).