Black basalt fragment
Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine
igneous
Category
Mineral Based Human Made Alloy
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Labradorite
(Ca,Na)(Al,Si)4O8 (Plagioclase Feldspar)
mineral
Bloodstone
Chalcedony quartz variety (SiO2) with inclusions
mineral
Moss Agate
Silicon dioxide (SiO2) with mineral inclusions
Mineral
Amethyst Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Mica Schist with Quartz
Mica Schist (primarily Muscovite or Biotite with Quartz)
metamorphic
Granite (River-worn Cobble)
Phaneritic Felsic Igneous Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)
igneous
Mica Schist
Schist (muscovite/biotite rich regional metamorphic rock)
metamorphic
Kambaba Jasper
Stromatolite / Fossilized Algae (Rhyolitic structure)
sedimentary
Lepidolite
K(Li,Al)3(Al,Si,3O10)(F,OH)2
mineral
Muscovite Mica (with Quartz)
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Fire Agate
Silicon Dioxide (SiO2) with layered Iron Oxide (Limonite/Goethite)
mineral
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Mica Specimen (Schist / Muscovite)
Muscovite / Biotite Mica (KAl2(AlSi3O10)(F,OH)2)
metamorphic
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si)4O10(F,OH)2)
mineral
Mica Schist
Schist (Crystalline metamorphic rock)
metamorphic
Quartz with Muscovite Mica
SiO2 with KAl2(AlSi3O10)(OH)2
mineral group
Greenshist / Chlorite Schist
Chlorite schist (contains (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)
metamorphic
Diorite
Diorite
igneous
Carnelian
Carnelian (Silicon Dioxide - SiO2)
mineral
Dyed Purple Agate
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Banded Agate (specifically Carnelian Agate / Sardonyx)
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Amethyst (Geode Fragment)
Silicon Dioxide with iron impurities (SiO2)
mineral
Fossil Shark Tooth
Otodus sp. (possibly Otodus obliquus)
fossil
Leopard Skin Jasper
Jasper (Silicon Dioxide with impurities), SiO2
sedimentary
Siltstone with iron staining
Siltstone (primarily SiO2 with FeO(OH) coatings)
sedimentary
Breccia
Sedimentary Breccia
sedimentary
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Epidosite (Epidote-rich rock)
Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
metamorphic
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
gemstone
Unakite (polished/tumbled)
Unakite, a hydrothermally altered granite composed mainly of epidote, pink potassium feldspar (orthoclase/microcline), and quartz
metamorphic
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Granite
Phaneritic Plutonic Igneous Rock (Granite)
igneous
Basalt with Quartz Infill
Basalt (Mafic Extrusive Volcanic Rock)
igneous
Granite
Granite (Felsic Plutonic Rock)
igneous
Basalt with Quartz/Zeolite Inclusions
Porphyritic Basalt (SiO2 with Aluminosilicates)
igneous
Chert (vuggy variety)
Microcrystalline silica (SiO2)
sedimentary
Dalmation Jasper (or Dalmation Stone)
Dalmation Stone (composed of Perthite, Quartz, and Arfvedsonite)
igneous
Epidote or Unakite Rock
Epidote-bearing rock / Ca2(Al,Fe)3(SiO4)3(OH)
metamorphic
Blue Apatite
Fluorapatite - Ca5(PO4)3F
mineral
Tumbled dark green stone, likely serpentine or greenstone
Serpentinite (hydrated magnesium silicate minerals, chiefly antigorite/lizardite); possible chlorite-rich greenstone
metamorphic