Mimetite (Pb₅(AsO₄)₃Cl) is the arsenate analog of pyromorphite — yellow to orange hexagonal crystals from oxidized lead-arsenic ore zones. The “campylite” variety forms characteristic barrel-shaped, curved crystals. Bayan Obo (Inner Mongolia) hosts notable specimens alongside REE-bearing minerals.
Key Facts
- Mohs hardness 3.5–4.
- Forms a continuous solid-solution series with pyromorphite (PO₄ ↔ AsO₄ substitution).
- Color ranges from pale yellow to bright orange to brown.
- Hexagonal prismatic or barrel-shaped (campylite) crystals.
- Distinguished from pyromorphite by typically more orange/brown hue and by chemistry only.
Notable Chinese Localities
Bayan Obo Mine (Inner Mongolia) is the principal Chinese source. Daoping (Guangxi) produces mimetite alongside pyromorphite.
Found at these Localities
- Mibladen Mining District (米布拉登铅矿区)
- Broken Hill (布罗肯希尔铅锌银矿)
- Lavrion (Laurium) (拉夫里翁古铅锌银矿)
- Bisbee (Warren District) (比斯比铜矿)
- Tsumeb Mine (楚梅布矿)
- Mina Ojuela, Mapimí (马皮米奥胡埃拉矿)
- Daoping Mine (道平铅锌矿)
- Bayan Obo Mine (白云鄂博)
- Inner Mongolia (内蒙古)
- Guangxi (广西)
