This is a photo of a pyrite “sun” (or “dollar”) from Illinois. These small coin-shaped specimens are found in compacted shale layers above or within coal deposits (1). If you look closely at the detail view, you can see the reflection from what look to be flakes of pyrite.
Approximate Photo Location (Side 2)
Field of view: ~7/16” x 11/16“ (11.4mm x 17.1mm)
Images in focus stack: 13
Image of the specimen and setup.
1. Wilson, G. (2015). Pyrite sun. Retrieved from Turnstone Geological Services Limited.
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