Serpentine
Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)
Metamorphic rock
Category
Mineraloid Like Synthetic Material
Browse mineraloid like synthetic material specimens identified by the Rock Identifier community.
Rough Aquamarine
Beryl (Be₃Al₂Si₆O‑₁•H₂O)
Mineral
Rainbow Obsidian
Volcanic glass (SiO2 - approximately 70% or more silicon dioxide)
Igneous
Ferruginous Sandstone (Ironstone)
Arenite with Limonite/Goethite cement
sedimentary
Jasper River Pebble
Silicon Dioxide (SiO2)
sedimentary (microcrystalline quartz)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Aragonite Star Cluster (or Aragonite Sputnik)
Aragonite (Orthorhombic Calcium Carbonate, CaCO3)
mineral
Jasper
Silicon Dioxide (SiO2) - Impure Variety of Chert
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Red Jasper
SiO2 (Silicon Dioxide with Iron inclusions)
sedimentary
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions), SiO2 + Fe2O3
sedimentary
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Red Sandstone
Arenite (ferruginous sandstone)
sedimentary
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
metamorphic
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Concrete with Exposed Aggregate
Anthropogenic conglomerate (Concrete)
man-made rock (sedimentary analogue)
Quartzite
Quartzite (primarily SiO2)
metamorphic
Mica Schist
Mica Schist (contains Muscovite/Biotite, Quartz)
metamorphic
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Sedimentary
Titanium-coated Metal Cube (Man-made Fidget Toy)
Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)
Mineral alternative / Synthetic
Man-made Blank Ammunition (Brass)
CuZn (Cartridge Brass - roughly 70% Copper, 30% Zinc)
Anticrystalline / Synthetic Alloy
Meteorite (Chondrite)
Stony Meteorite (Ordinary Chondrite)
igneous
Chert (Jasper-like)
SiO2 (Cryptocrystalline Quartz)
Sedimentary
Ferruginous Sandstone (Ironstone Conglomerate fragments)
Ferruginous clastic sedimentary rock (SiO2 cemented by Fe2O3)
sedimentary
Zebra Jasper
Tetragonal Silicon Dioxide (Quartz) with impurities
sedimentary
Quartz
Quartz (SiO2)
Mineral
Rose Quartz
Silicon Dioxide with traces of Titanium, Iron, or Manganese (SiO2)
mineral
Rose Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Chert (White/Light Tan)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Serpentinite
Serpentinite (Mg, Fe, Ni)₃Si₂O―(OH)₄
metamorphic
Chert (Iron-stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Quartz
Quartz (SiO₂)
Mineral
Brachiopod Fossil in Shale
Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)
sedimentary
Coquina
Bioclastic Limestone
sedimentary
Clay Brick
Ceramic structural unit (Al2O3·2SiO2·2H2O as precursor)
metamorphic (man-made/anthropogenic)
Quartz Geode/Cluster
Quartz (SiO2)
mineral
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)