Basalt with Iron Oxide staining
Basalt (Mafic volcanic rock)
igneous
Category
Anthropogenic (Man Made Product Subject To Geological Processes)
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Red Jasper (Opaque Chalcedony)
Jasper / Silicon Dioxide (SiO2) with Ferric Iron inclusions
mineral
Quartz (beads)
SiO2 (Silicon Dioxide)
Mineral
Veined Limestone
Calcite-veined Limestone (CaCO3)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Blue Chalcedony and Picture Jasper Beads
Blue Chalcedony (SiO2), Picture Jasper (SiO2)
Mineral
Coal
Bituminous Coal (organic sedimentary rock)
sedimentary
Chalk
Micrite (primarily Calcium Carbonate or CaCO3)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
sedimentary
Coal (Bituminous Coal)
Caustobiolith / Sedimentary Rock
sedimentary
Quartzite Pebble
Si02 (Metamorphosed Sandstone)
metamorphic
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide impurities, SiO2 + Fe2O3)
sedimentary
Bituminous Coal
Coal (Sedimentary Rock)
sedimentary
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Aragonite
Aragonite (Calcium Carbonate - CaCO3)
mineral
Coal
Anthracite or Bituminous Coal
sedimentary
Bituminous Coal
Organic sedimentary rock (humic coal)
sedimentary
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Quartz (Milky/Bull Quartz)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Greenstone / Serpentinite
Serpentinite (complex of Mg, Fe, Ni, Al, Zn, Mn silicate minerals including Antigorite, Lizardite, and Chrysotile)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Pink Quartzite
Silica (SiO2) - Metamorphic rock
metamorphic
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Hematite Nodule
Hematite (Fe2O3)
mineral
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
mineralogical simulant
Polished orbicular/porphyritic granite or breccia
Likely potassium-feldspar–quartz granite with amphibole/biotite and epidote; exact variety uncertain from the image
igneous
Quartz Vein Rock
Silicon Dioxide (SiO2)
mineral
Blue Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Weathered iron-rich rock fragment
Likely limonite/goethite-rich ironstone; exact identification requires testing
mineral
Snowflake Obsidian
Obsidian with Cristobalite inclusions (70–75% SiO2)
igneous
Sandstone
Sandstone (lithified sand)
sedimentary
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
mineral
Porphyritic Basalt (or Andesite) Pebble
Porphyritic Mafic Volcanic Rock
igneous
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Granite
Granite (a common rock type, not a single mineral species)
Igneous
Coal
Bituminous Coal / Anthracite
sedimentary
Quartz
Quartz (SiO₂)
Mineral
Coal (Anthracite or Bituminous)
Carbon (C) with varying hydrocarbon and mineral impurities
sedimentary