Pink crystal aggregates of the extremely rare mineral jerrygibbsite from the type and only one of three known localities known worldwide (Franklin Mine, New Jersey, United States of America). Associated minerals are orange zincite and black franklinite. Jerrygibbsite is a manganese silicate. — Photo: David Hospital · CC BY-SA 4.0
Jerrygibbsite
A rare manganese-zinc silicate discovered in 1984 by Pete Dunn and named for mineralogist Gerald Gibbs.
Intro adapted from Wikipedia (CC BY-SA).
Jerrygibbsite is an IMA-recognized mineral species in the silicate class, with the chemical formula Mn²⁺₉(SiO₄)₄(OH)₂.
It crystallizes in the orthorhombic crystal system (space group Pbn2_1). It is a member of the Humite structural group.
Key properties: Mohs hardness 5.5; specific gravity 4; Light pink streak; Vitreous luster; refractive index 1.781; optically biaxial.
IMA symbol Jgb, IMA status: approved, named in 1981.
Found in a metamorphosed stratiform Zn-Mn deposit.
It is found associated with Franklinite, willemite, zincite, sonolite, leucophoenicite, tephroite.
In honor of Professor Gerald V. Gibbs, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.