Transit Token (RTD Denver)
Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)
not a rock or mineral (anthropogenic material)
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Agate
Silicon Dioxide (SiO2) - variety Chalcedony
mineral
Heliotrope (Bloodstone)
Cryptocrystalline Quartz (SiO2) with inclusions of Hematite (Fe2O3)
mineral
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
metamorphic
Yellow Chalcedony
Silicon Dioxide (SiO2)
mineral
Chert (Agatized)
Silicon dioxide (SiO2)
sedimentary
Fluorite
Calcium Fluoride (CaF2)
mineral
Ocean Jasper
Spherulitic Chalcedony (SiO2)
sedimentary
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
mineral
Amethyst Geode
Silicon Dioxide (SiO2) with iron impurities
mineral
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Zebra Jasper
Silicon Dioxide (SiO2) with various inclusions
metamorphic/sedimentary
Clear Quartz Cluster
Silicon Dioxide (SiO2)
mineral
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
mineral
Optical Calcite (Iceland Spar)
Calcite (CaCO3)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Satin Spar (Selenite Gypsum Sphere)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
mineral
Chert (or Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Botryoidal Hematite (Kidney Ore)
Hematite (Fe2O3)
mineral
Green Jasper
Silicon Dioxide (SiO2) with iron silicate inclusions
sedimentary
Red Jasper (Polished)
Jasper (Iron-rich Microcrystalline Quartz, SiO2)
sedimentary
Specular Hematite
Hematite (Fe2O3)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)
Cryptocrystalline Quartz (SiO2) with inclusions
sedimentary
Honey Calcite
Calcium Carbonate (CaCO3)
mineral
Flexicalymene Trilobite Fossil
Flexicalymene meeki (Order Phacopida, Family Calymenidae)
sedimentary
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Geode with Goethite/Hematite
Silicon Dioxide (SiO2) with Iron Oxides
mineral
Red Jasper
Jasper (Silicate mineral - SiO2)
sedimentary
Banded Gneiss
Gneiss (complex metamorphic silicate rock)
metamorphic
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
sedimentary
Granite Gneiss with Garnet
Garnetiferous Gneiss
metamorphic
Dendritic Agate
Dendritic Agate (Silicon Dioxide with Manganese or Iron Oxide inclusions, SiO2)
mineral
Pyrite (on host rock)
Iron Sulfide (FeS2)
mineral
Quartz (specifically Clear Quartz or Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Red Jasper
Jasper (Silicon Dioxide with Hematite inclusions), SiO2
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Clear Quartz Crystal
Silicon Dioxide (SiO2)
mineral
Chert with Desert Varnish
Cryptocrystalline Quartz (SiO2) with Manganese/Iron oxide coating
sedimentary