Waterworn greenstone pebble
Likely serpentinite or chlorite-rich metamorphic rock; exact identification requires testing
metamorphic
Category
Industrial Byproduct (Anthropogenic Rock Like Material)
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Nickel coin (U.S. currency)
Cupronickel (75% Copper, 25% Nickel alloy)
man-made alloy (metallic)
Quartzite
Quartzite (SiO2)
metamorphic
Gneiss
Gneiss (High-grade regional metamorphic rock)
Metamorphic
Fire Agate
Silicon Dioxide (SiO2) with Goethite or Limonite inclusions
mineral
Quartz Vein with Host Rock (Greywacke/Siltstone)
Silicon Dioxide (SiO2) within Clastic Sedimentary/Metamorphic Matrix
metamorphic
Petrified Wood
Silicified Wood
fossil
Fossiliferous Limestone
Calcite-rich Fossiliferous Limestone (CaCO3)
sedimentary
Red Sandstone
Sandstone (lithic arenite / ferruginous sandstone)
sedimentary
Vesicular Basalt with Zeolite
Mafic volcanic rock with Hydrated Aluminosilicate minerals (Zeolite group)
igneous
Jasper River Pebble
Silicon Dioxide (SiO2)
sedimentary (microcrystalline quartz)
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Quartz with Muscovite Mica
SiO2 with KAl2(AlSi3O10)(OH)2
mineral group
Peridotite (Olivine/Peridot)
Peridotite (comprising (Mg,Fe)2SiO4)
igneous
Diorite (Salt and Pepper Rock)
Phaneritic Plutonic Diorite (Plagioclase Feldspar + Amphibole/Biotite)
igneous
Pyrite (on host rock)
Iron Sulfide (FeS2)
mineral
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite/Iron oxide impurities
sedimentary (chemical)
Blue calcite (probable)
Calcite, CaCO₃
mineral
Sandstone (Wonderstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Sapphire
Corundum (Al2O3)
mineral
Greenschist (Chlorite Schist)
Greenschist (Metamorphic rock dominated by chlorite, actinolite, and epidote)
metamorphic
Jasper-rich Quartzite with Quartz Veining
Silicon Dioxide (SiO2) with Ferric Oxide inclusions
metamorphic
Granitic Pegmatite with Tourmaline/Chlorite
Pegmatite
Igneous
Diamond (or Diamond Simulant)
Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia - ZrO2, Moissanite - SiC)
gemstone
Diamond
Diamond (C)
mineral
Lazulite Quartzite
Quartzite with Lazulite (SiO2 with (Mg,Fe)Al2(PO4)2(OH)2)
metamorphic
Fossiliferous Sandstone / Fossil Fragment
Fossiliferous Sedimentary Matrix with Indeterminate Fossil Material
fossil
Raw Agate (Rough Lake Superior Agate or Jasper-Chalcedony Nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Granite / Arkosic Sandstone (Coarse Igneous or Sedimentary Aggregate)
Granite / Quartz-Feldspar Aggregate
igneous
Green Quartzite / Quartz Pebble
SiO2 (Silicon Dioxide with inclusions)
metamorphic
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains)
sedimentary
Yellow Quartzite (Iron-Stained Quartzite)
Quartzite (SiO2 with Fe2O3 trace impurities)
metamorphic
Chert / Flint
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)
sedimentary
Coquina
Bioclastic Limestone
sedimentary
Ironstone (likely Ferruginous Siltstone/Sandstone)
Ferruginous sedimentary rock (FeOx-rich clastic)
sedimentary
Rough Garnet in Matrix
Almandine Garnet (Fe3Al2Si3O12)
mineral
Herkimer Diamond
Quartz (SiO2)
mineral
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
metamorphic
Limestone
Calcareous sedimentary rock (CaCO3)
sedimentary
Basalt
Basalt (Mafic volcanic rock)
igneous
Diamond
Carbon (C)
gemstone