American Mineralogist's Image Gallery

Okayamalite: Ca2B2SiO7

Comments: Intergrowth between crystalline okayamalite (a) and amorphous silica (b). Okayamalite here forms regular lamellae elongated along [001], typically 400 Å thick. The grainy area (c) corresponds to the graphite film..
Location: Skarn sample from the Arendal district, Sorlandet, Norway. (AmMin, v85:1508). Scale: See Image.
© American Mineralogist

Okayamalite: Ca2B2SiO7

Comments: Intergrowth between crystalline okayamalite (a) and amorphous silica (b). Okayamalite here forms regular lamellae elongated along [001], typically 400 Å thick. The grainy area (c) corresponds to the graphite film..
Location: Skarn sample from the Arendal district, Sorlandet, Norway. (AmMin, v85:1508). Scale: See Image.
© American Mineralogist

Ominelite: (Fe++,Mg)Al3BSiO9

Comments: Photomicrograph of thin-section (plain light) of zoned ominelite (omn) with quartz (qtz) and plagioclase (pl) in alkali feldspar. (AmMin 87:163).
Location: Misen River in Tenkawa, Yoshino, Nara Prefecture, Japan. Scale: Grain size 0.6 mm.
© American Mineralogist

Ominelite: (Fe++,Mg)Al3BSiO9

Comments: Photomicrograph of thin-section (plain light) of zoned ominelite (omn) with quartz (qtz) and plagioclase (pl) in alkali feldspar. (AmMin 87:163).
Location: Misen River in Tenkawa, Yoshino, Nara Prefecture, Japan. Scale: Grain size 0.6 mm.
© American Mineralogist

Orickite: CuFeS2·(H2O)

Comments: Black and white image of a polished section showing intergrown crystals of orickite in sodalite (dark). (AmMin 68:246).
Location: Mafic alkalic diatreme at Coyote Peak near Orick, Humboldt County, California, USA. Scale: Image size 0.44 mm.
© American Mineralogist

Orickite: CuFeS2·(H2O)

Comments: Black and white image of a polished section showing intergrown crystals of orickite in sodalite (dark). (AmMin 68:246).
Location: Mafic alkalic diatreme at Coyote Peak near Orick, Humboldt County, California, USA. Scale: Image size 0.44 mm.
© American Mineralogist

Paulkellerite: Bi2Fe+++(PO4)O2(OH)2

Comments: SEM photomicrograph of euhedral crystals of paulkellerite (AmMin, v73:870).
Location: Neuhilfe mine, Schneeberg, East Germany. Scale: See Image.
© American Mineralogist

Paulkellerite: Bi2Fe+++(PO4)O2(OH)2

Comments: SEM photomicrograph of euhedral crystals of paulkellerite (AmMin, v73:870).
Location: Neuhilfe mine, Schneeberg, East Germany. Scale: See Image.
© American Mineralogist

Paulmooreite: Pb2As+++2O5

Comments: Scanning electron photomicrograph of paulmooreite. AmMin v64:352.
Location: Langban,Varmland, Sweden. Scale: 150X Magnification.
© American Mineralogist

Paulmooreite: Pb2As+++2O5

Comments: Scanning electron photomicrograph of paulmooreite. AmMin v64:352.
Location: Langban,Varmland, Sweden. Scale: 150X Magnification.
© American Mineralogist

Phosphovanadylite: (Ba,Ca,K,Na)x[(V,Al)4P2(O,OH)16]·12(H2O) x~0.66

Comments: Scanning electron microscope micrographs showing the cubic habit of phosphovanadylite. (AmMin 83:890).
Location: Phosphoria Formation at Monsanto’s Enoch Valley Mine, Soda Springs, Idaho. Scale: Crystal size 40 µm.
© American Mineralogist

Phosphovanadylite: (Ba,Ca,K,Na)x[(V,Al)4P2(O,OH)16]·12(H2O) x~0.66

Comments: Scanning electron microscope micrographs showing the cubic habit of phosphovanadylite. (AmMin 83:890).
Location: Phosphoria Formation at Monsanto’s Enoch Valley Mine, Soda Springs, Idaho. Scale: Crystal size 40 µm.
© American Mineralogist

Piergorite-(Ce): Ca8Ce2(Al0.5 Fe+++0.5)([ ],Li,Be)2Si6B8O36(OH,F)2

Comments: B&W image of a group of platy-elongated crystals of piergorite-(Ce) on matrix.
Location: Tre Croci locality, Vetralla, Viterbo province, Italy. Scale: Crystal Length 400 µm.
© American Mineralogist

Piergorite-(Ce): Ca8Ce2(Al0.5 Fe+++0.5)([ ],Li,Be)2Si6B8O36(OH,F)2

Comments: B&W image of a group of platy-elongated crystals of piergorite-(Ce) on matrix.
Location: Tre Croci locality, Vetralla, Viterbo province, Italy. Scale: Crystal Length 400 µm.
© American Mineralogist

Polhemusite: (Zn,Hg)S

Comments: B&W polished section (PPL) image (green filter) of aggregates of polhemusite (P) in stibnite (S) with associated cinnabar (C) and quartz (Q). (AmMin, v63:1153).
Location: Mercury-bearing antimony ore from the B and B deposit, Big Creek district, Valley County, Idaho. Scale: Scale Bar 0.5 mm.
© American Mineralogist

Polhemusite: (Zn,Hg)S

Comments: B&W polished section (PPL) image (green filter) of aggregates of polhemusite (P) in stibnite (S) with associated cinnabar (C) and quartz (Q). (AmMin, v63:1153).
Location: Mercury-bearing antimony ore from the B and B deposit, Big Creek district, Valley County, Idaho. Scale: Scale Bar 0.5 mm.
© American Mineralogist

Poppiite: Ca2(V+++,Fe+++,Mg)(V+++,Al)2(Si,Al)3(O,OH)14

Comments: SEM micrograph of a poppiite crystal fragment (AmMin v91. p585).
Location: Gambatesa mine, near the village of Reppia (Val Graveglia, Northern Apennines, Italy). Scale: See Image.
© American Mineralogist

Poppiite: Ca2(V+++,Fe+++,Mg)(V+++,Al)2(Si,Al)3(O,OH)14

Comments: SEM micrograph of a poppiite crystal fragment (AmMin v91. p585).
Location: Gambatesa mine, near the village of Reppia (Val Graveglia, Northern Apennines, Italy). Scale: See Image.
© American Mineralogist

Protoanthophyllite: (Mg,Fe)7Si8O22(OH)2

Comments: Drill core showing white acicular crystalline aggregates of protoanthophyllite in matrix with a close up image on the right..
Location: Drill-core sample from the waste dump of the abandoned Takase chromite mine, Okayama Prefecture, Japan. Scale: Core size 3 cm.
© American Mineralogist

Protoanthophyllite: (Mg,Fe)7Si8O22(OH)2

Comments: Drill core showing white acicular crystalline aggregates of protoanthophyllite in matrix with a close up image on the right..
Location: Drill-core sample from the waste dump of the abandoned Takase chromite mine, Okayama Prefecture, Japan. Scale: Core size 3 cm.
© American Mineralogist