Chert (often called Flint when dark)
Microcrystalline silicon dioxide (SiO2)
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Chert (often called Flint when dark)
Microcrystalline silicon dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartzite with Hematite
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 inclusions)
Botryoidal Malachite
Malachite - Cu2CO3(OH)2
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Chert (specifically Jasper/Carnelian Agate)
Microcrystalline Quartz (SiO2)
Vesicular Basalt (Amygdaloidal)
Amygdaloidal Basalt (Mafic volcanic rock)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Turquoise (Blue Howlite imitation)
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Granite
Granite (Phaneritic Igneous Rock)
Limestone with Calcite Crystals
Calcium Carbonate (CaCO3)
Gold Nugget
Native Gold (Au)
Quartz Pebble
Silicon Dioxide (SiO2)
Agate
Agate (Silicon Dioxide - SiO2)
Malachite
Copper carbonate hydroxide, Cu2CO3(OH)2
Yellow Quartz Pebble (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Rainbow Hematite (Man-made/Treated)
Tumbled Hematite with Titanium/Anodized coating (Iron(III) oxide, Fe2O3)
Pyrite
Iron Disulfide (FeS2)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Chert (Nodular Chert)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Vesicular Basalt with Oxidation
Scoriaceous Olivine Basalt (Mafic volcanic rock)
Granite
Granite (composed of Quartz, Alkali Feldspar, and Plagioclase)
Turquoise (Tumbled/Polished)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Greenstone
Greenschist (containing chlorite, epidote, and actinolite)
Drupa Quartz (Sparkly Drusy Quartz on Matrix)
Crystalline Silicon Dioxide (SiO2) on host rock
Milky Quartz (among River Rock)
Quartz (Silicon Dioxide, SiO2)
Vesicular Basalt
Mafic Volcanic Rock (Basalt)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
Collection of Minerals and Ores
Various (e.g., Uraninite (U3O8), Carbon (C), Native Gold (Au), Hematite (Fe2O3), Galena (PbS), etc.)
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Quartz (Milky or Citrine-leaning)
Silicon Dioxide (SiO2)
N/A - Non-Geological Item
Quartz
Quartz (SiO₂)
K2 Jasper (K2 Granite)
Azulite in Granite (Quartz + Feldspar + Biotite + Azurite)
Granitoid (Granite/Gneiss)
Granitoid silicate rock, primarily quartz and feldspar
Basalt with Iron Oxidation
Mafic Igneous Rock (Basalt)
Fossiliferous Limestone (Crinoidal)
Bioclastic Limestone (predominantly CaCO3)
Brown Agate
Silicon Dioxide (SiO2)
Honey Calcite
Calcium Carbonate (CaCO3)