Citrine (Iron-stained Quartz)
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary (With Some Aspects Of Mineral Replacement)
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Sodalite
Sodalite - Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)
mineral
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcedony replacement)
Mineral / Fossil
Diamond (or Cubic Zirconia imitation)
Carbon (C) - Native Element
mineral
Sapphire
Corundum (Al2O3)
mineral
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
mineral
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
mineral
Peridot
Olivine ((Mg, Fe)2SiO4)
mineral
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Tumbled Obsidian (possibly Mahogany Obsidian variant)
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
igneous
Beads (likely glass or man-made material)
N/A (artificial material)
Man-made material, not a natural rock or mineral specimen
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
mineral
Amber
Amber (Succinite), fossilized tree resin
Mineraloid
Amber
Succinurite (C10H16O)
mineraloid
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
igneous
Mixed Quartz and River Pebbles (Stone Collection)
Mixed assortment containing mainly Silicon Dioxide (SiO2)
igneous, sedimentary, metamorphic, and mineral
Yellow Ochre / Limonite
Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)
mineral
Quartz (River Pebble)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Sunstone
Oligoclase (a variety of Plagioclase Feldspar) - (Na,Ca)(Si,Al)4O8
mineral
Mica (Muscovite)
Muscovite, KAl2(AlSi3O10)(OH)2
Mineral
Vesicular Basalt with Secondary Mineral Inclusions
Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Black Obsidian
Volcanic Glass (predominantly SiO2, Silicon Dioxide)
igneous
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
sedimentary
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2)
mineral
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Mineral
Schist
Mica Schist
metamorphic
Olivine (Peridot)
Olivine Group (Magnesium Iron Silicate), (Mg, Fe)2SiO4
mineral
Schorl (Black Tourmaline)
Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4
mineral
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
mineral
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Banded Gneiss (with possible weathered sulfide or iron staining)
Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides
Metamorphic
Peridot
Olivine (Mg, Fe)₂SiO₄
mineral
Coal (most likely Bituminous or Anthracite)
Coal (organic sedimentary rock)
Sedimentary
Almandine Garnet
Fe3Al2(SiO4)3
mineral
Aragonite
Aragonite (Calcium Carbonate - CaCO3)
mineral
Labradorite
(Ca, Na)(Al, Si)4O8 (Plagioclase Feldspar)
mineral
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Ferruginous Sandstone (Iron-rich Sandstone)
Ferruginous Arenite
sedimentary
Mahogany Obsidian
Volcanic Glass with Hematite inclusions (SiO2)
igneous
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Mineral
Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral.
Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.
mineral
Flint
Chert (a form of cryptocrystalline quartz, chemical formula SiO₂)
Mineral