Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Category
Mineral (Gemstone)
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Quartz (Chatoyant or Milky variety)
Silicon Dioxide (SiO2)
mineral
Purple cabochon gemstone, likely charoite
Charoite, a complex potassium-calcium silicate mineral; identification from the image is uncertain
gemstone
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Almandine Garnet
Almandine (Fe3Al2Si3O12)
mineral
Moonstone (Orthoclase Feldspar)
Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8)
mineral
Sapphire
Corundum (Al2O3)
gemstone
Fluorite
Calcium Fluoride (CaF2)
mineral
Garnet
Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
mineral
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
mineral
Red Garnet (likely Almandine)
Almandine (Fe3Al2(SiO4)3)
mineral
Peridot
Olivine ((Mg, Fe)2SiO4)
mineral
Weathered granitic or metamorphic rock fragment
Indeterminate; likely quartz–feldspar–mica-bearing granitoid or gneiss
igneous
Pegmatite (Quartz, Feldspar, and Tourmaline/Biotite)
Pegmatitic Igneous Rock
igneous
Olivine
(Mg,Fe)2SiO4
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon dioxide (SiO2)
Mineral
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
metamorphic
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Epidote
Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
mineral
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
mineral
Green Aventurine
Quartz (SiO2) with fuchsite inclusions
mineral
Prehnite
Ca2Al(AlSi3O10)(OH)2
mineral
Quartz
SiO2
mineral
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (KAlSi3O8)
mineral
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
mineral
Banded Agate (Lake Superior Agate style)
Cryptocrystalline Quartz (SiO2)
mineral
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
mineral
Amber
Succinite (a fossilized organic resin)
mineral
Ruby (Raw Corundum)
Corundum (Al2O3) with Chromium traces
mineral
Purple Fluorite Octahedron
Fluorite (Calcium Fluoride, CaF2)
mineral
Uncertain small polished gemstone or mineral
Indeterminate; likely quartz-family material, possibly druzy quartz or glass-like chalcedony
gemstone
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Mineral
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz-rich pegmatite, likely with iron staining
Granitic pegmatite, chiefly quartz (SiO₂) and feldspar, with possible mica and iron oxides
igneous
Microcline Feldspar
KAlSi3O8
mineral
Peridot (Olivine)
Olivine ((Mg, Fe)2SiO4)
mineral
Quartz Geode
Quartz (Silicon Dioxide, SiO2)
mineral