Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Category
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Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Porphyritic Basalt (Amygdaloidal)
Porphyritic Mafic Volcanic Rock (Amygdaloidal Basalt)
Crushed Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Mica (likely Muscovite)
Muscovite / KAl2(AlSi3O10)(OH)2
Sandstone (likely Iron-rich or Arkosic)
Arenite (SiO2 with FeO(OH) or Fe2O3 staining)
Quartzite
Quartzite (primarily SiO2)
Quartz (Milky or Cloudy variety)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Fluorite (Green Fluorite on Host Rock)
Fluorite (Calcium Fluoride, CaF2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (specifically Gray/Tan Bedded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Muscovite Mica
Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))
Basalt (River Pebble)
Extrusive mafic igneous rock
Green Aventurine
Aventurine (variety of Quartz - SiO2)
Rough Aquamarine
Beryl (Be₃Al₂Si₆O‑₁•H₂O)
Basalt (Amygdaloidal)
Amygdaloidal Basalt
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
Scoria (Vesicular Basalt)
Scoria (Extrusive Igneous Rock)
Labradorite (Larvikite variety)
Feldspar (Plagioclase series), (Na,Ca)(Si,Al)4O8
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Ocean Jasper (Orbicular Jasper)
Silicon Dioxide (SiO2) - Variety of Chalcedony/Quartz
Pyrite
Iron Sulfide (FeS2)
Puddingstone
Conglomerate (Indurated)
Schist
Mica Schist (primarily Muscovite and Quartz)
Peridot
Olivine (Mg, Fe)2SiO4
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Labradorite
Labradorite ((Ca,Na)(Al,Si)4O8)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Garnet (specifically Almandine or Pyrope)
Almandine (Fe3Al2Si3O12) or Pyrope (Mg3Al2Si3O12)
Biotite / Black Mica
Biotite K(Mg,Fe)3AlSi3O10(F,OH)2
Green Quartz (Prasiolite variant or Aventurine)
Silicon Dioxide (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Sandstone
Arenite (primarily SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Fulgurite
Liesegang (Fulgurite)
Quartzite (specifically an iron-stained or Carnelian-colored variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Diorite (Polished Cobble)
Diorite (Intermediate intrusive igneous rock)
Pyrite
Iron Disulfide (FeS2)
Chert (Arrowhead)
Chert (primarily Microcrystalline Silica, SiO2)
Serpentinite
Serpentinite (composed primarily of minerals in the Serpentine group)