Weathered chert or flint nodule
Microcrystalline quartz (SiO₂), commonly chalcedony/quartz
sedimentary
Category
Sedimentary Or Igneous (Host Environment)
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Pyrite
Iron Sulfide (FeS2)
mineral
Quartz Vein in Host Rock (Breccia/Rhyolite)
Silicon Dioxide (SiO2) with matrix
Mineral in Igneous/Sedimentary host
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
mineral
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Quartz crystal with Pyrite inclusions
Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)
mineral
Shale
Lutaceous Sedimentary Rock
sedimentary
General Gravel (River Rock/River Stones)
Mixed Lithic Sediments (Conglomerate Clasts)
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Apatite
Calcium phosphate fluoride/chloride, Ca5(PO4)3(F,Cl,OH)
mineral
Apatite
Calcium phosphate fluoride/chloride, Ca5(PO4)3(F,Cl,OH)
mineral
Quartz Geode Pebble
Silicon Dioxide (SiO2)
sedimentary
Chert (Agatized/Banded)
Chert (Microcrystalline Silicon Dioxide, SiO2)
sedimentary
Weathered Sandstone or Siltstone
Sedimentary Rock
sedimentary
Chalcedony with Matrix
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Greenstone
Hydrothermal Quartz (SiO2) with Chlorite/Epidote Schist host rock
metamorphic
Foliated Gneiss (River-Worn Pebble)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Quartz-bearing pegmatite or feldspar-rich rock
Likely granitic pegmatite composed mainly of quartz (SiO₂) and feldspar, with possible mica or iron-oxide staining
igneous
Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral / Sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Gold Ore in Matrix
Native Gold (Au) in Quartz/Limonite host rock
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) vein cutting through host rock
mineral
Pyrite-bearing Rock / Pyrite Ore
Iron Sulfide (FeS2) in host rock matrix
mineral
Chert
Chert (SiO2)
sedimentary
Ferruginous Quartz / Iron-Stained Quartz
Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)
mineral
Polished dark-speckled igneous pebble, likely diorite or gabbro
Probable diorite (plagioclase feldspar and hornblende/biotite); exact identification is uncertain from the image
igneous
Amber-bearing Coal/Sedimentary Rock
Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)
sedimentary
Granite Cobble / River Pebble
Granite (felsic intrusive igneous rock)
igneous
Jasper with Quartz Veining
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Bivalve Shell Fragment (Biogenic Calcite/Aragonite)
Calcium carbonate (CaCO3, primarily aragonite/calcite)
sedimentary
Chert (within Limestone matrix)
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Chert Nodule in Limestone (Flint in Chalk)
SiO2 (Microcrystalline Quartz) in CaCO3 (Calcite)
sedimentary
Likely hematite-bearing ironstone
Hematite (Fe₂O₃), possibly mixed with other iron oxides and host rock
mineral
Chert / Flint Conglomerate
Silicified Sedimentary Breccia (primarily SiO2)
sedimentary
Folded Schist / Gneiss (Metamorphic Rock)
Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)
metamorphic
Likely garnet crystal (rough fragment)
Garnet group; possibly almandine, Fe₃Al₂(SiO₄)₃
mineral
Polished garnet cabochon (likely almandine)
Almandine garnet, Fe₃Al₂(SiO₄)₃ (tentative identification)
gemstone
Blue Apatite
Fluorapatite / Apatite (Ca5(PO4)3(F,Cl,OH))
mineral
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
mineral
Gneiss (Cobble)
Gneiss
metamorphic
Pyrite
Iron Sulfide (FeS2)
mineral