:Locality: Nuestra Señora del Carmen Mines, Jumilla, Murcia, Spain Size: 2.8 × 2.2 × 2 cm Description: Rich aggregates of yuanfuliite needle like crystals, with orange-red color. They are accompanied by globular and brilliant calcite and hematite. From this classic Spanish locality — Photo: Joan Rosell , from rosellminerals.com · CC BY-SA 4.0
Yuanfuliite
A black magnesium-iron borate of metamorphosed magnesium marble, named for geologist Yuan Fuli.
Intro adapted from Wikipedia (CC BY-SA).
Yuanfuliite is an IMA-recognized mineral species in the borate class, with the chemical formula Mg(Fe³⁺,Al)O(BO₃).
It crystallizes in the orthorhombic crystal system (space group Pnma). It is a member of the Warwickite structural group.
Key properties: Mohs hardness 5–6; Black streak; Submetallic to adamantine luster; optically biaxial.
IMA symbol Yfl, IMA status: approved, named in 1994.
Found in metamorphosed magnesian marble in a boron deposit (Zhuanmiao deposit, China); in ultramafic rocks (Inglefield Land, Greenland).
It is found associated with Suanite, anhydrite, apatite (Zhuanmiao deposit, China); sinhalite, forsterite, calcite (Huayuangou deposit, China); forsterite, pleonaste, phlogopite.
In honor of Professor Yuan Fuli (1893–1987), Chinese geologist, China University of Geosciences, Wuhan, China.