pyroxene

Spinifex metakomatiite (serpentinite) (Neoarchean, 2711-2719 Ma; near Pyke Hill, Ontario, Canada) 6
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 7
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 8
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 11
by James St. John

Olivine-bearing anthill sediments (Black Rock, Leucite Hills, Wyoming, USA) 2
by James St. John

Actinolite xenolith in sandorite lamprophyre (Sandor Dike, Neoarchean, 2.703 Ga; Route 17 roadcut northeast of Wasp Lake & north of Wawa, Ontario, Canada) 14
by James St. John

Chromite & serpentine (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 2
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 15
by James St. John

Pilot Butte (Pliocene madupite lamproite volcanic center in the Leucite Hills, Wyoming, USA) 16
by James St. John

Wyomingite (Lower Pleistocene, 0.95 Ma; quarry on volcanic cone on Zirkel Mesa, Leucite Hills Volcanic Province, Wyoming, USA) 14
by James St. John

Kyanitic eclogite (Late Cretaceous, 90-95 Ma; Pohorje Mountains, Slovenia) 6
by James St. John

Magnetite-ilmenite (Mesoproterozoic, ~1155 Ma; mine at Tahawus/Sanford Lake, New York State, USA) 10
by James St. John

Monchiquite lamprophyre dike (Precambrian; Michipicoten River Bridge South roadcut, south of Wawa, Ontario, Canada) 38
by James St. John

Gabbro (Duluth Complex, Mesoproterozoic, 1099 Ma; Rt. 1 roadcut between Heart Lake & Little Spring Lake, Minnesota, USA) 4
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 10
by James St. John

Boar's Tusk (Early Pleistocene wyomingite volcanic center in the Leucite Hills, Wyoming, USA) 22
by James St. John

Spinifex metakomatiite (Upper Komatiitic Unit, Kidd-Munro Assemblage, Neoarchean, 2.711-2.719 Ga; Pyke Hill, near the Potter Mine, east of Timmins, Ontario, Canada) 16
by James St. John

Llao Rock (Crater Lake Caldera, Oregon, USA) 21
by James St. John

Meta-gabbro (Kings River Ophiolite, Early Ordovician, ~484 Ma; Fresno County, California, USA) 2
by James St. John

Calc-silicate rocks & reaction rim with metabentonite (Gouverneur Marble, Mesoproterozoic, ~1.1 Ga; Route 11 roadcut southwest of Canton, New York State, USA) 1
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 13
by James St. John

Pilot Butte (Pliocene madupite lamproite volcanic center in the Leucite Hills, Wyoming, USA) 17
by James St. John

Monchiquite lamprophyre dike (Precambrian; Michipicoten River Bridge South roadcut, south of Wawa, Ontario, Canada) 40
by James St. John

Gabbro (Duluth Complex, Mesoproterozoic, 1099 Ma; Rt. 1 roadcut between Heart Lake & Little Spring Lake, Minnesota, USA) 2
by James St. John

Actinolite xenolith in sandorite lamprophyre (Sandor Dike, Neoarchean, 2.703 Ga; Route 17 roadcut northeast of Wasp Lake & north of Wawa, Ontario, Canada) 8
by James St. John

Basalt (McCartys Flow, Holocene, ~2.4 to 3.9 ka; southeast of Grants, New Mexico, USA) 17
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 12
by James St. John

Anorthosite (Poe Mountain Anorthosite, Mesoproterozoic, 1.43 Ga; Sybille Canyon, Laramie Range, Wyoming, USA) 4
by James St. John

Monchiquite lamprophyre dike (Precambrian; Michipicoten River Bridge South roadcut, south of Wawa, Ontario, Canada) 41
by James St. John

Olivine-bearing anthill sediments (Black Rock, Leucite Hills, Wyoming, USA) 4
by James St. John

Gabbro (Duluth Complex, Mesoproterozoic, 1099 Ma; Rt. 1 roadcut between Heart Lake & Little Spring Lake, Minnesota, USA) 3
by James St. John

Olivine-bearing anthill sediments (Black Rock, Leucite Hills, Wyoming, USA) 1
by James St. John

Glaucophane-bearing schist (Attic-Cycladic Crystalline Complex, Cretaceous to Eocene metamorphism, 78 to 42 Ma; Siphnos Island, Aegean Sea) 7
by James St. John

Gabbro with granite dike (Devonian; Hulls Cove, Mt. Desert Island, Maine, USA) 2
by James St. John

Granite dike in anorthosite (Poe Mountain Anorthosite, Mesoproterozoic, 1.43 Ga; Sybille Canyon, Laramie Range, Wyoming, USA) 2
by James St. John

Boar's Tusk (Early Pleistocene wyomingite volcanic center in the Leucite Hills, Wyoming, USA) 21
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 16
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 37
by James St. John

"Greek Green Porphyry" (glomeroporphyritic metabasalt) (Tyros Beds, Triassic; near Levetsova, Laconia, Greece) 1
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 23
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 5
by James St. John

Madupite lamproite (Late Pliocene, 3 Ma; Pilot Butte volcanic center, Leucite Hills, Wyoming, USA) 14
by James St. John

Sybille Canyon (Laramie Range, Wyoming, USA) 1
by James St. John

Diorite (Devonian; Hulls Cove, Mt. Desert Island, Maine, USA) 4
by James St. John

Re-exhumed sub-fossil trees (died late 1700s) (Sandy River, Oxbow Park, Oregon, USA) 48
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 103
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 19
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 1
by James St. John

Yooperlite (sodalite syenite) (Lake Superior shoreline, Upper Peninsula of Michigan, USA) 8
by James St. John

Olivine-bearing anthill sediments (Black Rock, Leucite Hills, Wyoming, USA) 3
by James St. John

Ordinary chondrite (New Concord Meteorite) 16
by James St. John

Eclogite (Late Silurian to Early Devonian, ~400-423 Ma; Almenningen, Vestland, Norway) 23
by James St. John

Xenoliths in monchiquite lamprophyre dike (Precambrian; Michipicoten River Bridge South roadcut, south of Wawa, Ontario, Canada) 4
by James St. John

Magnetite-ilmenite (Mesoproterozoic, ~1155 Ma; mine at Tahawus/Sanford Lake, New York State, USA) 12
by James St. John

Porphyritic shoshonite (Denver Formation, 63-64 Ma, Lower Paleocene; Table Mountain, Golden, Colorado, USA) 1
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 30
by James St. John

Ordinary chondrite (New Concord Meteorite) 5
by James St. John

Troctolite (Laramie Anorthosite Complex, Mesoproterozoic; Sybille Pit, Laramie Range, Wyoming, USA) 3
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 14
by James St. John

Inch-scale layering of plagioclase feldspar and pyroxene (Stillwater Complex, Neoarchean, 2.71 Ga; near the Stillwater Mine, Beartooth Mountains, Montana, USA) 35
by James St. John