Concrete with Aggregate
Artificial Conglomerate (Cement and Aggregate)
Category
Browse mineral pseudomorph specimens identified by the Rock Identifier community.
Concrete with Aggregate
Artificial Conglomerate (Cement and Aggregate)
Gneiss (Banded Gneiss)
Gneiss
Botryoidal Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Sandstone (likely Arkosic or Lithic)
Clastic Sedimentary Rock (SiO2 with accessory minerals)
Banded Gneiss
Gneiss (Foliated Metamorphic Rock)
Granite
Granite (composed mainly of Quartz, Potassium Feldspar, Plagioclase, and Biotite/Mica)
Gneiss (specifically Granite Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Small pale mineral fragment
Unidentified; possibly quartz, calcite, or feldspar
Epidote
Epidote (Ca2(Al2,Fe3+)AlSi3O12(OH))
Serpentine (likely serpentinite)
Serpentine-group minerals, chiefly antigorite, lizardite, and/or chrysotile; commonly with magnetite and minor brucite
Turquoise and Hematite
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)
Limonite Ironstone
Goethite-Limonite concretion / Iron oxide
Small weathered fossil or mineral fragment
Indeterminate; possibly fossilized shell, bone, or a pale carbonate mineral
Banded Sandstone (Beach Pebble)
Quartz Arenite Sandstone
Schist
Schist (various mineral compositions)
Devil's Toenail (Fossil Oyster)
Gryphaea arcuata (Calcium Carbonate, CaCO3)
Serpentinite
Serpentine-group minerals, chiefly antigorite, lizardite, and chrysotile; approximate formula Mg3Si2O5(OH)4
Pebble with vesicles, likely basalt
Vesicular basalt; chiefly plagioclase, pyroxene, and iron-magnesium minerals
Limonite with Pyrite
Hydrated Iron Oxide Hydroxide, FeO(OH)·nH2O
Fossil shark tooth, likely sand tiger shark
Fossilized selachian tooth; possibly *Carcharias* or *Striatolamia*
Shark Tooth Fossil
Carcharodon / Otodus fossilized tooth (Calcium Phosphate / Hydroxyapatite)
Fossilized Shark Tooth
Chondrichthyes (Class)
Milky quartz (rough quartz crystal)
Quartz, silicon dioxide (SiO₂)
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (KAlSi3O8)
Mica / Muscovite or Biotite
Phyllosilicate mineral group (e.g., KAl2(AlSi3O10)(OH)2)
Chalcopyrite (Peacock Ore)
Chalcopyrite (CuFeS2)
Botryoidal Chalcedony / Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Mica (Muscovite or Biotite)
Sheet silicate mineral group (e.g., KAl2(AlSi3O10)(F,OH)2)
Feldspar
Aluminosilicate (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
Quartz with Sulfide Inclusions
Silicon Dioxide (SiO2) with metallic mineral inclusions
Quartz (Druzy)
Silicon Dioxide (SiO2)
Ruby (Raw Corundum)
Corundum (Al2O3) with Chromium traces
Granite
Granite (felsic intrusive igneous rock)
Tumbled agate/chalcedony
Microcrystalline quartz (SiO₂), likely mossy or dendritic agate with iron-oxide inclusions
Fluorite
Calcium Fluoride (CaF2)
Talc Schist / Soapstone
Talc (Mg3Si4O10(OH)2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)