streak test
The streak test is a dignostic test for hematite, gray or red.
Basically, the streak test examines the powder of a mineral. Usually it is done by rubbing the specimen in question against a piece of unglazed porcelin. As long as the mineral is softer than the "streak plate" it will leave a powdered line. It is especially useful for iron minerals and other oxides or sulfides. I keep a streak plate in my vest pocket while in the field.
I believe we are seeing a percentage of powdered hematite in the RAT debris from the ground sphereoids.
great pictures!