All of the quartz stones will test in the quartz/citrine level on the tester. Amethyst,citrine,smoky,clear,prasiolite/green,etc. The vast majority...
Citrine is quartz.
Natural hematite is not magnetic.
Looks like a nice Pyrite crystal ring,have you tested the ring shank for gold?
It looks like slag in the photo...... https://sites.wustl.edu/meteoritesite/items/glassy-vesicular/
We found a lot of the stones in Virginia years ago, my sons gave most of them to their friends........
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