Images
Formula: Mn2+9(SiO4)4(OH)2
Nesosilicate (insular SiO4 groups),
leucophoenicite subgroup,
humite group,
orthorhombic paramorph of monoclinic
sonolite,
manganese-bearing mineral
Crystal System: Orthorhombic
Specific gravity: 4.00 measured, 4.07 calculated
Hardness: 5½
Streak: Pale pink
Colour: Violet pink to pinkish violet
Common impurities: Fe,Zn,Mg,Ca,H2O
Environments
Jerrygibbsite occurs in a metamorphosed zinc-manganese
deposit (Webmin).
Leucophoenicite and sonolite are
common associates
(Mindat).
At the Wessels mine, Kalahari manganese field, South Africa, jerrygibbsite is intimately intergrown with
leucophoenicite and sonolite
(Dana).
At the type locality, the Franklin Mine, Sussex county, New Jersey, USA, jerrygibbsite occurs in a metamorphosed
manganese-bearing zinc silicate and
zinc oxide ore deposit (Mindat). It occurs in contact with
franklinite, willemite,
zincite and sonolite. In one of the type
specimens jerrygibbsite is associated with, but not seen to be in contact with,
leucophoenicite. On another specimen jerrygibbsite occurs in contact with
sonolite (AM 69.546-552). The assemblages are notable for the lack of any
calcium-bearing species. Jerrygibbsite appears to be a phase which requires zinc for its stability
(AM 70.379-387).
Back to Minerals