A confession: I know NOTHING about geology or gems. But this stuff is amazing. (A rare moment of humility. This wine stuff works.i find this color enticing.and i know the reason, but i cannot speak to it.
Strengite is a rare iron phosphate mineral with the formula: FePO₄ · (or sometimes containing some Al, but not to be confused with Variscite, and so can also be written with the formula: (Fe,Al)PO₄ · )