Porphyritic Igneous Rock / Granite or Rhyolite Porphyry
Porphyritic intrusive/extrusive igneous rock
igneous
Category
Igneous Or Sedimentary (Anthropogenic Modification)
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Porphyritic Igneous Rock / Rhyolite Porphyry
Porphyritic volcanic rock
igneous
Porphyritic Igneous Rock / Porphyry
Porphyry (Plagioclase/Quartz phenocrysts in a finer-grained groundmass)
igneous
Porphyritic Granite (Pink Granite)
Granite (plagioclase, alkali feldspar, quartz, biotite)
igneous
Rounded granite cobble
Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, potassium feldspar, plagioclase, and minor mica or amphibole
igneous
André Landed Here Rock (Glacial Erratic)
Granodiorite / Diorite (compositional estimate)
igneous
Granite and Igneous Rock Collection
Intrusive igneous rock / Granitoid
igneous
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Metamorphic Rock
Hematite (beads)
Hematite (Fe₂O₃)
Mineral
Granite Pebble
Granitoid (Plagioclase, Alkali feldspar, Quartz, Biotite/Amphibole)
igneous
Granite Boulder
Phaneritic Felsic Igneous Rock
igneous
Pink Granite Pebble
Granite
igneous
Pink Granite
Phaneritic Igneous Rock (Quartz-Feldspar-Mica)
igneous
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
igneous
Botryoidal Chalcedony
Chalcedony (SiO2)
Mineral
Basalt
Extrusive Igneous Rock
igneous
Muscovite Mica
Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2
Mineral
Quartz (possibly milky quartz or quartz with inclusions)
SiO2 (Silicon Dioxide)
Mineral
Calcite
Calcite (CaCO₃)
Mineral
Biotite (Black Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
mineral
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
mineral
Rose Quartz
Silicon Dioxide with trace inclusions of dumortierite or titanium (SiO2)
mineral
White Topaz
Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2
mineral
Ruby in Zoisite
Ruby (α-Al2O3) embedded in Zoisite (Ca2Al3(SiO4)3(OH)) with some Hornblende
Metamorphic Rock (composed of multiple minerals)
Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)
Chalcedony (SiO₂)
Mineral (or mineraloid if microcrystalline)
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Mineral
Biotite Schist (likely)
Biotite Schist (rock), Biotite (mineral)
Metamorphic
Banded Gneiss (River Cobble)
Gneiss (a high-grade metamorphic rock)
metamorphic
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Rock (likely Sedimentary)
Plagioclase Feldspar (specifically Albite/Oligoclase)
(Na,Ca)(Si,Al)4O8
mineral
Quartz (Smoky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO₂)
Mineral
Diorite
Diorite
igneous
Basalt
Extrusive Igneous Rock
igneous
Quartz
Silicon Dioxide (SiO2)
Mineral
Feldspar-rich igneous rock, likely granite or gneiss fragment
Granite-like quartz–feldspar rock; exact identification is uncertain from the blurred image
igneous
Rounded dark igneous pebble, likely basalt
Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, with possible olivine
igneous
Wishing Stone (Quartz-Veined Basalt)
Amygdaloidal Basalt with Quartz (SiO2) vein
igneous
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Granite Pebble
Felsic Intrusive Igneous Rock
igneous