River Stone (likely Basalt or Gabro)
Mafic Igneous Rock
igneous
Category
Sedimentary Rock (Possibly Composed Of Various Minerals)
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Likely weathered river pebble
Indeterminate lithology; possibly fine-grained sandstone, siltstone, or chert
sedimentary
Tumbled quartz-rich rock, likely quartzite or milky quartz with iron-oxide staining
Quartzite (primarily SiO₂), possibly with hematite/goethite staining and minor feldspar or mica
metamorphic
Granite
Felsic intrusive igneous rock
igneous
Fossil Shark Tooth
Otodus sp. (possibly Otodus obliquus)
fossil
Bivalve Fossil (Internal Mold)
Bivalvia (Phalladomya or similar genus)
fossil
Chalcedony (Agate) Pebble
Silicon Dioxide (SiO2)
mineral
Dark mafic igneous rock, likely basalt or gabbro
Basalt–gabbroic rock; chiefly plagioclase feldspar and pyroxene, possibly olivine and iron oxides
igneous
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Fluorite
Calcium Fluoride (CaF2)
mineral
Banded Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Bloodstone
Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)
Metamorphic Rock
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Metallic sulfide ore, likely galena-bearing rock
Galena (lead sulfide, PbS), possibly with pyrite or other sulfides
mineral
Granite
Intrusive Igneous Rock (Felsic)
igneous
Chert (Banded)
Cryptocrystalline Silica (SiO2)
sedimentary
Rose Quartz
Rose Quartz (SiO2)
Mineral
Nuummite
Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz-veined Limestone
Sedimentary limestone with quartz/calcite veinlets
sedimentary
Gneiss
Gneiss (Metamorphic rock)
metamorphic
Granite (Weathered/Oxidized)
Phaneritic Felsic Igneous Rock (composed of Quartz, Orthoclase Feldspar, and Mica)
igneous
Common Opal
SiO2·nH2O (Hydrated Silicon Dioxide)
mineraloid
Iron Meteorite (Individual)
Siderite (composed of Kamacite and Taenite minerals)
igneous
Shale or Siltstone
Fine-grained siliciclastic sedimentary rock
sedimentary
Rough Quartz (Milky / Clear Quartz)
Silicon Dioxide (SiO2)
mineral
Gneiss
Gneiss
metamorphic
Granite Water-Worn Pebble
Intermediate to Felsic Phaneritic Igneous Rock
igneous
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Diamond (set in jewelry)
Carbon (C)
mineral
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mineral
Granite
Intrusive Igneous Rock
igneous
Basalt
Extrusive igneous rock
igneous
Slate
Foliated Metamorphic Rock (composed of quartz, illite, chlorite)
metamorphic
Bornite (“peacock ore”), likely weathered copper sulfide
Bornite, Cu₅FeS₄; possibly chalcopyrite, CuFeS₂, with iridescent tarnish
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Mineral
Basalt
Mafic Igneous Rock (composed primarily of pyroxene and calcium-rich plagioclase)
igneous
Mineral and Rock Collection (Assorted)
Mixed collection including Quartz (SiO2), Jasper (SiO2 with impurities), Rose Quartz, and Aventurine
mineral
Dyed Dalmatian Jasper (Dalmatian Stone)
Perthitic Feldspar with Arfvedsonite inclusions
igneous
Hag Stone
Perforated Sedimentary Rock (typically Sandstone or Siltstone)
sedimentary