Conglomeratic gravel / polymictic breccia
Polymictic rudite, likely anthropogenic or beach/stream gravel; composition varies
sedimentary
Category
Man Made Material (Anthropogenic 'Mineraloid')
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Asphalt (Bituminous Concrete)
Bituminous Concrete / Pavement
man-made (synthetic rock)
Chert (flint) fragment
Microcrystalline quartz (SiO₂), commonly called chert or flint
sedimentary
Trilobite fossil
Trilobita (exact species indeterminable from the image)
fossil
Weathered iron-rich rock, possibly jasper or ironstone
Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests
mineral
Onyx (Black) and Mother of Pearl Inlay
Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl
mineral
Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Anthropogenic (Man-made material processed by nature)
Sea Glass (Turquoise/Aqua)
Amorphous Silica (SiO2) with transition metal dopants
Anthropogenic (Man-made material processed by nature)
Diamond ring
Diamond, crystalline carbon (C)
gemstone
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
mineral
Chert (Cherty Shale / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Chert / Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically Jasper or Flint)
Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Rounded gray pebble, likely quartzite
Quartzite (predominantly crystalline quartz, SiO₂); identification is tentative from the image
metamorphic
Chert Nodule
Microcrystalline Quartz (SiO2)
sedimentary
Chert (often called Flint in archaeological contexts)
Silicon Dioxide (SiO2)
sedimentary
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Rough Diamond
Pure Carbon (C)
mineral
Chert (specifically Flint)
Chert (SiO2)
sedimentary
Chert (Polished River Pebble)
Chert (SiO2)
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Red agate bead (likely dyed or treated)
Agate, a microcrystalline variety of quartz; SiO₂
gemstone
US Penny
Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy
Man-made object (metal alloy)
Chert
Silicon dioxide (SiO2)
Sedimentary
Polished stone sphere, possibly agate or jasper
Likely microcrystalline quartz (SiO₂); exact variety cannot be confirmed from the image
mineral
Tumbled serpentine
Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; approximately Mg₃Si₂O₅(OH)₄
metamorphic
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
mineral
Yellow-orange amber
Fossilized tree resin; amber is an organic mineraloid, not a true mineral
fossil
Tumbled amber
Amber (fossilized plant resin), commonly succinite; organic mineraloid
gemstone
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Tumbled greenstone, likely nephrite jade
Nephrite jade (interlocking tremolite–actinolite amphibole; Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)
metamorphic
Chert (Siltstone / Flint)
SiO2 (Cryptocrystalline Quartz)
sedimentary
Asphalt (Bituminous Concrete)
Composite material (bitumen binder with mineral aggregate)
man-made rock (technosol)
Blue-green chrysocolla rough specimen
Chrysocolla, hydrated copper aluminosilicate; commonly associated with malachite, quartz, and limonite
mineral
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Likely flint pebble (possibly a worked flint fragment)
Microcrystalline quartz (chalcedony), SiO₂; commonly called flint
sedimentary
Slag (Industrial Glass/Metal)
Ferrous slag or Glassy silicate byproduct
Antropogenic rock (Man-made)