Barium-pharmacosiderite (bariopharmacosiderite), a barium ferric-iron arsenate hydroxide hydrate mineral, was described from Sterling Hill by Peacor and Dunn (1985); it has not been found at Franklin. It occurs as deep yellow, 0.3 mm, equant crystals, which are rough-surfaced and pseudo-octahedral in habit.
The luster of barium-pharmacosiderite is vitreous. The observed ratio of Ba:Fe:As is 0.8:7.6:6.0. It occurs rarely on the 340 level at Sterling Hill on younger pharmacosiderite, which overlies ogdensburgite.
Another yellow pharmacosiderite, occurring in 1 mm, yellow, cubic to pseudoprismatic crystals, was found at Sterling Hill, and preserved by John Baum, but is not properly any of the known mineral species in the pharmacosiderite series. Sr is the dominant large cation, but appreciable amounts of Pb, Mn, and Zn are also present; it is chemically inhomogeneous. The compositional range for Pb and Sr is PbO 3.4-7.4, SrO 1.8-3.1 wt. %; other cations present (Ba,Ca,Zn,Fe, As,Mn) are relatively invariant. It occurs associated with willemite, koettigite, and sphalerite in a vein assemblage. (Dunn, 1995)

 Location Found: Ogdensburg
 Formula: Ba0.5Fe43+(AsO4)3(OH)4 · 5H2O
 Essential Elements: Arsenic, Barium, Hydrogen, Iron, Oxygen
 All Elements in Formula: Arsenic, Barium, Hydrogen, Iron, Oxygen
 IMA Status: Approved 1990
 To find out more about this mineral at minDat's website, follow this link   Bariopharmacosiderite

Dunn, Pete J. (1995). Franklin and Sterling Hill New Jersey: the world's most magnificent mineral deposits. Franklin, NJ.: The Franklin-Ogdensburg Mineralogical Society. p.659. 'Barium-pharmacosiderite'

No Images at this time.


All content including, but not limited to, mineral images, maps, graphics, and text on the Franklin-Ogdensburg Mineralogical Society, Inc. (FOMS) website is licensed under a
Creative Commons Attribution-NonCommercial 4.0 International License.
Creative Commons License