Ele Willoughby, PhDHaüyne, formed in magma chambers, is pretty, blue & can fluoresce. But electrically conductive iron-ore hematite is an absolute giant of art history, used as red ochre, going back at least 164,000 years to Pinnacle Point Caves! Also called Venetian, mars or English red.
Vote hematite! #MinCup25
Vote here: https://www.mineralcup.org/2025/vote/r3m01
CCochard