Not sure of the chemistry here, but it appears to be pyrite altered to goethite, then partially altering to hematite. Or possibly the other way round. All with a bit of relict quartz. Ex Jo Price Collection. Width of view 6mm. Stack of 45 images.
Click on the image below for a higher resolution version.
![](https://pebblecollection.com/wp-content/uploads/2024/03/ncat-JP3354-Hematite-after-Pyrite-Mount-Goldsworthy-Shay-Gap-De-Grey-Station-Port-Hedland-Shire-Western-Australia-6mm-45-wp-1024x682.jpg)