Glauconitic Sandstone (Greensand)
Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Glauconitic Sandstone (Greensand)
Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)
Ferruginous Sandstone (Grit)
Clastic Sedimentary (Ironstone-rich Sandstone)
Ferruginous Sandstone (Ironstone)
Ferruginous Sandstone / Limonite-cemented Quartz Sandstone
Chert (varieties include Flint or Jasper)
Chert (cryptocrystalline quartz; SiO₂)
Garnet (specifically Almandine)
Almandine - Fe3Al2(SiO4)3
Jasper (Tumbled)
Silicon Dioxide (SiO₂)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Sandy Ironstone
Ferruginous Sandstone
Septarian Nodule (Dragon Stone)
Septarian (composed of Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)
Limestone
Calcium Carbonate (CaCO3)
Banded Flint (Polished Stripe Flint)
Silicon Dioxide (SiO2) - variety of Chert
Pink Botswana Agate
Silicon Dioxide (SiO₂), a cryptocrystalline variety of Quartz and Chalcedony
Blue Chalcedony (Tumbled)
Silicon Dioxide (SiO2)
Seraphinite
Clinochlore (Mg,Fe)5Al(AlSi3O10)(OH)8 - specific variety for Seraphinite due to its fibrous inclusions and chatoyancy.
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Lapis Lazuli
Complex metamorphic rock consisting mainly of Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite
Coquina
Coquina (a type of limestone)
Pyrite
Iron Sulfide (FeS2)
Blue Chalcedony
Silicon Dioxide (SiO2)
Banded Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Optical Calcite (Iceland Spar)
Calcium Carbonate (CaCO3)
Fluorite (Green Fluorite)
Calcium Fluoride (CaF2)
Sandstone with Iron Oxide (Limonite/Hematite)
Ferruginous Sandstone (SiO2 with FeO(OH)·nH2O)
Limonite (Iron Ore)
Limonite (Hydrous ferric oxides), generic formula FeO(OH)·nH2O
Pyrite
Pyrite (Iron Disulfide), FeS2
Jade (likely Nephrite or Jadeite)
Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)
Silicon Dioxide (SiO2) with iron inclusions
Jasper
Silicon dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (specifically Yellow/Common Opal or Jasper mixture)
Silicon Dioxide (SiO2)
Chert (often called Flint or Jasper based on color)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Septarian Nodule (Septarian Dragon Stone)
Septarian Concretion (CaCO3 + Al2Si2O5(OH)4)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (and Jasper pebble)
Microcrystalline Silica (SiO2)
Chert / Jasper
Silicon Dioxide (SiO₂)
Chert (Red/Pink Jasper subtype)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone with trace fossil
Sandstone, possibly with Skolithos or similar trace fossil
Agate / Banded Chalcedony
Agate (Silicon Dioxide / SiO2)
Sandstone
Quartz Sandstone (predominantly)
Pink Sapphire
Corundum (Al2O3 with trace Chromium and Iron)