Coquina
Bioclastic Limestone (composed primarily of CaCO3)
sedimentary
Category
Man Made
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Exposed aggregate concrete (stone-chip surface)
Portland-cement concrete containing natural aggregate; not a natural rock
sedimentary
Sandstone (Water-worn Cobble)
Arenite (SiO2 with CaCO3 or Fe2O3 cement)
sedimentary
Turquoise
Hydrous phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
gemstone
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
mineral
Diamond
Diamond (pure Carbon, C)
mineral
Fossilized echinoid (sea urchin), likely a flint/chalk-associated test
Echinoid fossil; likely a regular echinoid such as Echinocidaris or related taxon, composed mainly of recrystallized calcite (CaCO₃)
fossil
Diabase (Dolerite)
Diabase / Dolerite
igneous
Goldstone (aventurine glass)
Synthetic copper-bearing soda-lime glass; commonly sold as red goldstone
gemstone
Fossilized Coral (Coquina/Limestone)
Cnidaria Anthozoa (Fossilized)
sedimentary
Land Snail Shell
Gastropoda (Calcium Carbonate, CaCO3)
fossil
Engineered Quartz (Quartzite look-alike)
Silicon Dioxide (SiO2) composite
mineral-based composite
Chert (White Chert/Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Tumbled brown chalcedony or agate
Microcrystalline quartz (SiO₂), likely chalcedony; possibly iron-stained jasper or agate
gemstone
Peanut Wood (Fossilized Wood in Radiolarite)
Petrified Wood (Silicified)
fossil
Pearl (Biogenic Mineraloid)
Calcium carbonate (CaCO3) primarily as Aragonite
mineral
Gypsum (Satin Spar / Alabaster variety)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
mineral
Chert (Flint / Quartz Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Flint
SiO2 (Cryptocrystalline Quartz)
sedimentary
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
igneous
Lava Rock (Dyed)
Basalt / Volcanic scoria
igneous
Beaded gemstone bracelet
Indeterminate; likely small polished mineral beads, possibly turquoise or dyed stone, with metal and glass components
gemstone
Diamond (or Cubic Zirconia)
Carbon (C) or Zirconium Dioxide (ZrO2)
gemstone
Coquina
Biogenic Limestone (Coquina)
sedimentary
Vesicular Basalt (or Scoria)
Vesicular Basalt
igneous
Siltstone Pebble
Siltstone (composed of microscopic quartz and clay minerals)
sedimentary
Tumbled chert or jasper pebble
Microcrystalline quartz (SiO₂), likely chert/jasper
sedimentary
Polished greenstone/serpentine pebble (probable)
Serpentinite, dominated by serpentine-group minerals (lizardite/chrysotile); possible accessory olivine or chlorite
metamorphic
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Belemnoit (Fossil)
Belemnoidea (Order), Rostrum / Guard
sedimentary
Diamond
Carbon (C)
mineral
Rutilated Quartz
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions
mineral
Granodiorite
Intrusive Igneous Rock
igneous
Granite / Diorite (Granodiorite)
Granodiorite / Quartz Diorite
igneous
Tumbled brown chalcedony (likely jasper or agate)
Microcrystalline quartz, SiO₂; chalcedony with iron-oxide staining
mineral
Slate
Metamorphic Pelitic Rock
metamorphic
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Diamond
Diamond (pure carbon C)
mineral
Diamond
Carbon (C)
mineral
Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite
mineral