Rare new mineral with a very curious tubular shape which gives name to the mineral. The sample has one perfect tube and it is associated to hairy metallic rings that are also tubulite. From: Bio Mine, Borgofranco, Torino, Piedmont, Italy. — Photo: David Hospital · CC BY-SA 4.0
Tubulite
Tubulite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula Ag₂Pb₂₂Sb₂₀S₅₃.
It crystallizes in the monoclinic crystal system.
Key properties: Metallic luster.
IMA symbol Tub, IMA status: approved, named in 2011.
Found in sulfide and sulfosalt-bearing veins of quartz, barite, calcite, dolomite and siderite, cutting metamorphosed volcano-sedimentary rocks (Le Rivet, France) or in metamorphosed clastic sedimentary rocks (Biò, Italy).
It is found associated with Galena, boulangerite (Le Rivet); geocronite, bournonite, fizélyite (Biò).
The name refers to its appearance, as it occurs as thin micro-tubes.