Mineral Specimen Images (F)

Foordite: Sn++(Nb,Ta)2O6

Comments: Brownish massive foordite.
Location: Manono, Shaba (Katanga), Congo (Zaïre). Scale: Picture size 7 mm.
© Thomas Witzke / Abraxas-Verlag

Footemineite: Ca2Mn++Mn++2Mn++2Be4(PO4)6(OH)4·6H2O

Comments: Yellow, barrel-shaped, prismatic footemineite crystal (AmMin v93:2.
Location: Foote Lithium Co. Mine (Foote Mine), Kings Mountain District, Cleveland Co., North Carolina, U.S.A. Scale: Crystal size 0.8 mm.
© American Mineralogist

Fornacite: Pb2Cu(CrO4)(AsO4)(OH)

Comments: Dark, prismatic crystals of fornacite on matrix.
Location: El Khun mine, Anarak, Iran. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Fornacite: Pb2Cu(CrO4)(AsO4)(OH)

Comments: Emerald green platy crystals to 0.75mm on a pink to white, siliceous matrix.
Location: Lone Star mine, Copperopolis, Yavapai County, Arizona. Scale: Picture size 1.4 cm.
© Tom Loomis / Dakota Matrix

Forsterite: Mg2SiO4  
Olivine: (Mg,Fe)2SiO4

Comments: Peridot (Forsterite) recrystallized at the base.
Location: Skardu, Nooristan, Pakistan. Scale: 2.5 x 2.7 cm.
© Fabre Minerals

Foshagite: Ca4Si3O9(OH)2

Comments: Tan to gray fibrous to columnar aggregate of foshagite.
Location: Crestmore Quarry, Riverside County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Foshallasite: Ca3Si2O7·3(H2O)

Comments: Pearly translucent white somewhat fibrous aggregate of foshallasite.
Location: Mount Yukspor, Khibiny Massif, Kola Peninsula, Murmansk District, Russia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Fourmarierite: Pb(UO2)4O3(OH)4·4(H2O)

Comments: Thick tabular orange crystals of fourmarierite.
Location: Shinkolobwe mine, Tantara, Shaba, Democratic Republic of the Congo. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Fraipontite: (Zn,Al)3(Si,Al)2O5(OH)4  
Zaccagnaite: Zn4Al2(OH)12(CO3)·3(H2O)

Comments: Scanning electron microscope image of hexagonal, tapering, prismatic zaccagnaite crystals, covered by a thin crust of fraipontite. (AmMin 86:1294).
Location: Marble quarries of the Carrara basin (Apuan Alps, Italy). Scale: See Image.
© American Mineralogist

Fraipontite: (Zn,Al)3(Si,Al)2O5(OH)4  
Zinalsite: Zn2AlSi2O5(OH)4·2(H2O) (?)  
Smithsonite: ZnCO3

Comments: Pearly white, sub-mm fraipontite (zinalsite) crystals associated with green smithsonite.
Location: Lavrion District Mines, Lavrion District, Attikí (Attica; Attika) Prefecture, Greece. Scale: Specimen Size 1.4 x 1.0 x 0.9 cm.
© Rob Lavinsky

Francevillite: (Ba,Pb)(UO2)2V2O8·5(H2O)  
Chervetite: Pb2V2O7

Comments: Bottle brown tabular crystals of chervetite on yellow francevilleite.
Location: Mounana, Haut-Ogoue, Gabon. Scale: Size Not Given.
© Lou Perloff / Photo Atlas of Minerals

Francevillite: (Ba,Pb)(UO2)2V2O8·5(H2O)  
Curienite: Pb(UO2)2V2O8·5(H2O)

Comments: Intense yellow curienite and orange francevillite.
Location: Mouonana, Haut-Ogoue, Gabon. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Francevillite: (Ba,Pb)(UO2)2V2O8·5(H2O)

Comments: Specimen of orange francevillite with minor yellow curienite.
Location: Mouana Mine, Gabon. Scale: Crystal size 4 mm.
© John Veevaert

Francevillite: (Ba,Pb)(UO2)2V2O8·5(H2O)  
Mounanaite: PbFe+++2(VO4)2(OH)2

Comments: Stout, yellow, transparent, prismatic, striated crystals of francevillite on brownish red mounanaite matrix.
Location: Mounana mine, Franceville, Haut-Ogooué, Gabon. Scale: Picture size 1.5 cm.
© Paul M. Schumacher

Franciscanite-III: Mn++6V+++++2Si2(O,OH)14

Comments: Dark reddish brown large franciscanite grains to 1.5cm in tan-colored gageite matrix.
Location: Pennsylvania mine, Santa Clara Co., California, USA. Scale: 5.5 x 4 x 3cm.
© Tom Loomis / Dakota Matrix

Francisite: Cu3Bi(SeO3)2O2Cl

Comments: Greenish crusts of francisite on matrix.
Location: Baccu Locci Mine, Villaputzu, Cagliari Province, Sardinia, Italy. Scale: Picture size 3.5 mm.
© Thomas Witzke / Abraxas-Verlag

Francisite: Cu3Bi(SeO3)2O2Cl

Comments: Fine acicular crystals of green francisite to 0.1mm on matrix.
Location: Iron Monarch iron mine, Iron Knob, South Australia, Australia. Scale: Picture size 1.5 cm.
© Tom Loomis / Dakota Matrix

Franckeite: (Pb,Sn)6Fe++Sn2Sb2S14

Comments: Massive franckeite with pockets of small .5 mm crystals.
Location: Animas Mine, Atocha-Quechisla district, Sud Chichas Province, Potosí Department, Bolivia. Scale: 25x20x15 mm.
© John Betts - Fine Minerals

Franckeite: (Pb,Sn)6Fe++Sn2Sb2S14  
Potosiite: Pb6Sn2FeSb2S14

Comments: Visually indistinguishable metallic potosiite/franckeite crystals to 6 mm..
Location: San Jose mine, Oruro City, Oruro Department, Bolivia. Scale: Crystal size 6 mm.
© Rob Lavinsky

Francoanellite: H6(K,Na)3(Al,Fe+++)5(PO4)8·13(H2O)

Comments: Chalky massive francoanellite.
Location: Giottodi Castellana Cave, Puglia, Italy. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species