Likely iron-rich rock or weathered metallic mineral fragment
Uncertain; possibly limonite/goethite or iron-bearing slag
mineral
Category
Anthropogenic Material (Man Made Rock)
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Sandstone (specifically Arkose or Quartz Arenite)
Arenite (primarily SiO2 with possible Feldspar)
sedimentary
Cobalt Blue Slag Glass
Amorphous Silicon Dioxide (anthropogenic) with Cobalt additives
mineraloid
Coquina
Bioclastic Limestone
sedimentary
Blue Goldstone
Synthetic Aventurescent Glass (Cobalt-doped soda-lime glass)
man-made glass
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Coquina / Fossiliferous Limestone
Calcareous bioclastic sedimentary rock (CaCO3)
sedimentary
Diamond (as set in a metal alloy ring)
Diamond (Pure Carbon, C)
mineral
Sea Glass
Amorphous silicon dioxide (Man-made glass weathered by nature)
mineral
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Titanium Aura Quartz (Aura Quartz)
Titanium-coated Silicon Dioxide (SiO2)
mineral
Diamond
Native Carbon (C)
gemstone
Blue Goldstone
Aventurine Glass (SiO2 with Cobalt/Copper inclusions)
man-made glass
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Basalt
Basalt
Igneous
Moissanite
Silicon Carbide (SiC)
mineral
Dyed Quartz Geode
Silicon Dioxide (SiO2) with artificial pigment
mineral
Conglomerate (Asphaltic/Anthropogenic)
Clastic sedimentary rock / Bituminous mixture
sedimentary
Hematite Beads
Hematite (Fe2O3)
Mineral
Probable amber fragment
Amber (fossilized plant resin; chiefly amorphous organic resin, commonly dominated by succinite)
gemstone
Ruby in Matrix
Corundum (Al2O3)
mineral
Coquina
Bioclastic Limestone
sedimentary
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Chert or Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
igneous
Green Glass Slag
Amorphous Silicon Dioxide (SiO2) with metal oxide impurities
mineraloid (man-made)
Lapis lazuli and green-blue chalcedony jewelry
Lapis lazuli: lazurite-bearing metamorphic rock, chiefly lazurite (Na₃Ca(Al₃Si₃O₁₂)S) with calcite and pyrite; second stone: likely chrysoprase or green-blue chalcedony (microcrystalline quartz, SiO₂)
gemstone
Chert (varietal: Flint/Jasper)
Silicon Dioxide (SiO2)
sedimentary
Chert (Arrowhead variety)
Chert (SiO2)
sedimentary
Coquina
Bioclastic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Dark rounded pebble, likely basalt or slag
Probable fine-grained mafic rock; possibly basalt (plagioclase–pyroxene) or industrial iron/steel slag
igneous
Slag
Anthropogenic Vitreous Silicate / Ferro-silicate Slag
igneous
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Organic Gemstone/Biomineral
Green glassy mineral specimen, likely rough emerald or green fluorite
Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph
mineral
Tumbled chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
mineral
Diamond
Carbon (C)
gemstone
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert
Chert (SiO2)
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary