Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Category
Synthetic Material (Not A Rock Or Mineral)
Browse synthetic material (not a rock or mineral) specimens identified by the Rock Identifier community.
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Phyllite
Phyllite (Foliated metamorphic rock)
metamorphic
Diorite
Phaneritic intermediate plutonic rock
igneous
Siltstone
Siltstone (Clastic Sedimentary Rock)
sedimentary
Weathered river pebble, likely quartz-rich sandstone or iron-stained quartzite
Provisional identification: quartz-rich sandstone/quartzite; exact composition cannot be confirmed from the image
sedimentary
Fulgarite
Fulgurite (Lechatelierite / Vitrified Sand)
igneous
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Fossiliferous Limestone with Crinoid Stem fragment
Calcite (CaCO3) containing Crinoidea fossils
sedimentary
Chert (or Chalcedony) Nodule
Microcrystalline Quartz (SiO2)
sedimentary
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
metamorphic
Pumice
Pumice (Volcanic Rock)
igneous
Milky quartz (likely weathered quartz vein)
Quartz, silicon dioxide (SiO₂)
mineral
Green aventurine quartzite (likely)
Quartz-rich metamorphic rock; predominantly microcrystalline quartz (SiO₂), with possible fuchsite, chlorite, or epidote
metamorphic
Rounded dark river pebble
Likely basalt or fine-grained andesite; exact identification requires testing
igneous
Quartzite Pebble
Metamorphic Quartzite (SiO2)
metamorphic
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
sedimentary
Ironstone (likely Limonite or Goethite)
Ferruginous sedimentary rock (FeO(OH)·nH2O)
sedimentary
Conglomerate with Native Copper
Clastic Sedimentary Rock with Native Copper (Cu)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Diorite (Salt and Pepper Rock)
Diorite
igneous
Chert (Black Flint)
Silicon Dioxide (SiO2)
sedimentary
Riverstone Quartzite
Quartzite (primarily SiO2)
metamorphic
Mica Schist with Garnet
Garnetiferous Mica Schist
metamorphic
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Sandstone
Arenite (primarily SiO2 with Fe2O3)
sedimentary
Black tumbled stone, likely basalt or black jasper
Most consistent with fine-grained basalt (mainly plagioclase and pyroxene); exact identification requires testing
igneous
Crushed Limestone (Gravel)
Calcium Carbonate (CaCO3)
sedimentary
White Marble
Recrystallized Calcite (CaCO3) / Marble
metamorphic
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities
mineraloid
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Vesicular basalt (scoria-like volcanic rock)
Basalt; primarily plagioclase, clinopyroxene, and olivine, with abundant vesicles
igneous
Tumbled green-and-white stone, likely serpentine
Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile), commonly with magnetite and carbonate veins
metamorphic
Tumbled greenish serpentine
Serpentinite; chiefly antigorite/lizardite, Mg₃Si₂O₅(OH)₄
metamorphic
Slag
Anthropogenic Vitrophyre (Iron or Smelting Slag)
Mineral-like byproduct
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Serpentine
Antigorite, Lizardite, or Chrysotile; Mg3Si2O5(OH)4
metamorphic
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Basalt with Xenolith
Extrusive Igneous Rock containing Mantle Xenolith
igneous
Conglomerate
Conglomerate (Sedimentary rock containing rounded clasts)
sedimentary
Quartzite Cobble
Quartzite (SiO2)
metamorphic