Sandstone (with prominent jointing/fractures)
Arenite (composed primarily of SiO2)
Category
Browse organic (if resin) or synthetic (if glass); simulating sedimentary or metamorphic (for natural stones) specimens identified by the Rock Identifier community.
Sandstone (with prominent jointing/fractures)
Arenite (composed primarily of SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Stiped Slate Beach Pebble
Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)
Dyed Dragon Vein Agate
Silicon Dioxide (SiO2) with artificial pigment
Shale
Fissile Mudstone (primarily composed of clay minerals and quartz)
Travertine
Calcareous Tufa / Travertine (CaCO3)
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
Chalcedony (Agate/Quartz)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Quartz Vein in Gneiss or Basalt
Milky Quartz (SiO2) within Metamorphic Host Rock
Blue Sapphire (in a faceted jewelry setting)
Corundum (Al2O3) with trace Iron and Titanium
Ferruginous Sandstone (Ironstone)
Sedimentary rock with Limonite/Goethite cement
Quartzite Pebble
Quartzite (primarily SiO2)
Unknown Organic Object (likely a berry or fruit)
Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.
Slag (Industrial Glassy Byproduct)
Ferro-silicate Slag
Glauconitic Sandstone
Glauconitic Quartz-Wacke / Sandstone (Fe(II),Fe(III),Al,Mg)2-3(Si,Al)4O10(OH)2
Shale
Shale (Consolidated fine-grained clay/silt)
Slag (Industrial Glass)
Anthropogenic Vitreous Slag (Post-industrial byproduct)
Sandstone
Arenite (primarily SiO2)
Slate
Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)
Quartz Pebble (often referred to as 'Sea Glass' or 'River Stone' when worn smooth)
Silicon Dioxide (SiO2)
River Cobble (likely Quartzite or Limestone)
SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
Sandstone (with Iron Oxide)
Arenite with Limonite/Hematite staining
Corundum (Sapphire/Ruby in Matrix)
Aluminium oxide (Al2O3)
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
Rough Quartz (Grey-Green)
Silicon Dioxide (SiO2)
Yellow Quartzite (River Pebble)
Quartzite (SiO2)
Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
Chert (Fossiliferous)
Silicon Dioxide (SiO2)
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
Quartzite Pebble
Quartzite (primarily SiO2)
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Sandstone (Ferruginous)
Arenite (variable SiO2 with Fe2O3 staining)
Conglomerate
Conglomerate (Sedimentary rock)
Chert (Jasper/Chalcedony)
Microcrystalline Silica (SiO2)
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (SiO2)
Basalt River Stone
Basalt
Quartz Vein in Host Rock
Hydrothermal Quartz (SiO2) in Slates/Schists