Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
Category
Browse sedimentary rock (possibly composed of various minerals) specimens identified by the Rock Identifier community.
Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)
Red Quartzite River Stone
Metamorphic Rock (composed mainly of Quartz, SiO2)
Banded Gneiss
Gneiss (Metamorphic high-grade rock)
Sandstone with Liesegang Rings
Arenite with Iron Oxide Liesegang Banding
Greywacke (River/Beach Pebble)
Greywacke (Impure Sandstone)
Quartzite
Quartzite (primarily SiO2)
Basalt
Basalt
Ruby in Zoisite
Ruby (Corundum, Al2O3) in Zoisite (Calcium aluminum silicate hydroxide, Ca2Al3(SiO4)3(OH)) with some Hornblende
Gneiss
Metamorphic rock of high-grade regional metamorphism
Hypersthene (or Enstatite/Ferrosilite)
Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)
Mixed Quartz and Jasper Pebbles
Silicon Dioxide (SiO2)
Fossilized Coral
Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)
Leopard Skin Jasper
Chalcedony (cryptocrystalline Quartz)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Fossilized Coral (Petoskey Stone type)
Hexagonaria percarinata (Fossilized Rugose Coral)
Marble
Recrystallized Calcite / Dolomite (CaCO3)
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
Pyrite (Cube variety)
Iron Sulfide (FeS2)
Galena
Galena (Lead Sulfide), PbS
Limonite-stained Quartz / Quartzite
Silicon Dioxide (SiO2) with iron hydroxides (FeO(OH)·nH2O)
Carnelian
Carnelian Agate (Silica: SiO2)
Malachite
Copper Carbonate Hydroxide [Cu2CO3(OH)2]
Septarian Nodule Segment (Commonly known as Dragon Stone or Lightning Stone)
Septarian Nodule (CaCO3 / Hydrated Calcium Carbonate)
Fluorite
Fluorite (Calcium Fluoride - CaF2)
Quartzite
Quartzite (SiO2)
Zircon
Zircon (ZrSiO4)
Sandstone
Arenite (primarily SiO2)
Pyrite
Iron Sulfide (FeS2)
Marble
Metamorphosed Limestone (main mineral: Calcite, CaCO3)
Marble
Recrystallized Calcite (CaCO3)
Quartzite
Quartzite (primarily SiO2)
Basalt
Extrusive mafic igneous rock
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Hematite
Hematite (Fe2O3)
Red Jasper (Jasper)
Silicon Dioxide (SiO₂)
Mahogany Obsidian
Volcanic glass (SiO2 + Fe2O3)
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Banded Gneiss
Gneiss (Metamorphic high-grade, predominantly SiO2, Al2O3, K2O, Na2O)
Granodiorite (or Granite) Pebble
Phaneritic Felsic Igneous Pebble
Quartz (Common or Milky)
Silicon Dioxide (SiO2)
Granite
Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)