What is Minium?
Minium brings an intense red accent to an ore-mineral cabinet. Its colour is not merely decorative: it reflects mixed lead valence and the high-temperature or oxidising conditions that produced the coating.
Mineralogy and crystal structure
Reference formula: Pb3O4. Minium is a red mixed-valence lead oxide containing Pb(II) and Pb(IV). Its vivid colour can occur as an earthy coating, but the heavy lead-rich composition and association with other lead oxides are central to identification. Minium is classified with oxides and has a tetragonal crystal system. Typical hardness is 2.5–3 on the Mohs scale and specific gravity is approximately 8.3–8.9.
Colour, lustre and habit
Typical colours include scarlet, red, orange-red. The usual granular, massive, powdery habit and adamantine, earthy, vitreous lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Minium forms in or is associated with oxidation of lead ores and high-temperature alteration of galena or litharge. Important documented localities include the United States, Spain, Germany, France, Australia and Mexico.
Scarlet colour in a lead-oxide suite
Minium brings an intense red accent to an ore-mineral cabinet. Its colour is not merely decorative: it reflects mixed lead valence and the high-temperature or oxidising conditions that produced the coating.
Collecting and care
Lead-bearing and toxic as dust: keep sealed, avoid cutting or grinding, and wash hands after handling.
