Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Category
Antropogenic (Man Made)
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Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Sandstone (Pebble)
Sandstone (arenite, arkose, wacke depending on composition)
sedimentary
Jasper
Silicon dioxide (SiO2) with impurities
sedimentary
Quartzite
Metamorphic Rock (Mainly SiO2)
metamorphic
Obsidian (Black)
Obsidian (High-silica volcanic glass)
igneous
Diabase (Greenstone)
Diabase (Dolerite)
igneous
Fossil crinoid columnal in limestone
Crinoidea indet.; calcitic ossicle (CaCO₃)
fossil
Likely flint pebble (possibly a worked flint fragment)
Microcrystalline quartz (chalcedony), SiO₂; commonly called flint
sedimentary
Sandstone
Arenite
sedimentary
Jade bangle
Likely nephrite jade (actinolite–tremolite amphibole); possibly jadeite
gemstone
Sandstone (specifically Arkose or Quartz Arenite)
Arenite (primarily SiO2 with possible Feldspar)
sedimentary
Turquoise cabochon ring
Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O
gemstone
Red Sandstone
Arenite (with Iron Oxide / Hematite staining)
sedimentary
Limestone
Calcareous sedimentary rock (CaCO3)
sedimentary
Fossilized sea urchin
Echinoid test, likely a regular sea urchin; calcite (CaCO₃)
fossil
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Fossilized echinoid (sea urchin), likely a sand dollar fragment or small regular urchin
Echinodermata; commonly Clypeasteroida or Echinoida, preserved mainly as calcite (CaCO₃)
fossil
Weathered iron-rich rock, possibly jasper or ironstone
Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests
mineral
Dyed Blue Agate Slice
Silicon Dioxide (SiO2)
mineral
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Sedimentary
Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Granite
Granite (felsic intrusive igneous rock)
igneous
Possible ironstone concretion or weathered mineral nodule
Iron-oxide-rich concretion, likely goethite/limonite; identification uncertain from the photo
sedimentary
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Mineral
Limonite (Iron Ore)
Hydrous Iron Oxide (goethite, lepidocrocite)
Mineral
Granite Cobble/Pebble
Granite
Igneous
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
igneous
Granite
Granite (a plutonic rock)
Igneous
Bog Iron / Limonite Concretion
Goethite/Limonite mixture (FeO(OH)·nH2O)
sedimentary
Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)
Chalcedony (SiO₂)
Mineral (or mineraloid if microcrystalline)
Iron-rich concretion or slag-like mineral fragment
Likely limonite/goethite (FeO(OH)·nH₂O), possibly magnetite-bearing material
mineral
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Granodiorite
Granodiorite
Igneous
BROWN GRANITE (likely 'Tan Brown' or similar)
Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)
igneous
Granite (weathered pebble)
Granite (plutonic igneous rock)
Igneous
Red-orange sunstone (likely aventurine feldspar) bead bracelet
Feldspar, commonly oligoclase or labradorite with copper inclusions; composition varies by source
mineral
Nephrite Jade
Nephrite
Mineral/Rock
Note on Image Identification: Textile
N/A (Anthropogenic material)
not a rock
Faience and Carnelian in Egyptian Revival Jewelry
Faience (quartz frit) and Carnelian (chalcedony, SiO2)
gemstone