Agate (specifically Chalcedony nodule)
Silicon Dioxide (SiO2)
Category
Browse organic (if resin) or synthetic (if glass); simulating sedimentary or metamorphic (for natural stones) specimens identified by the Rock Identifier community.
Agate (specifically Chalcedony nodule)
Silicon Dioxide (SiO2)
Yellow Quartzite River Stone
Quartzite (primarily SiO2)
Sandstone (likely Arkosic or Lithic)
Clastic Sedimentary Rock (SiO2 with accessory minerals)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Sandstone Beach Pebble
Clastic sedimentary rock (SiO2 with iron oxide cement)
Jasper with Agate and Quartz Inclusions
Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate
Chert Nodule (with Flint core)
Sedimentary Cryptocrystalline Quartz (SiO2)
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Basalt (Polished)
Basalt (Mafic Extrusive Igneous Rock)
Unidentifiable Rock Fragment
Zebra Jasper
Silicon Dioxide (SiO2) with various inclusions
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Sandstone
Arenite (Siliclastic sedimentary rock, primarily SiO2)
Shale with Plant Fossils / Carbonaceous Shale
Laminated Mudrock (Siliciclastic)
Sandstone
Arenite (primarily SiO2)
Turquenite (Dyed Howlite)
Dyed Ca2B5SiO9(OH)5 (Calcium Borosilicate Hydroxide)
Smoky Quartz
Silicon Dioxide (SiO2)
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Yellow Quartzite or Yellow Jasper
Quartzite (primarily SiO2 with Iron oxide staining)
Chert (Arrowhead or Projectile Point)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Titanium Quartz (Rough)
Titanium-included Silicon Dioxide (SiO2 + Ti)
Yellow Calcite
Calcium Carbonate (CaCO3)
Yellow Quartzite Pebble
Metamorphosed Sandstone (SiO2 with iron oxide impurities)
Sandstone
Arenite (composed primarily of SiO2)
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
Sandstone (Quartzite Pebble)
Arenite (primarily SiO2)
Quartz River Cobble (Yellow Jasper/Quartzite variant)
Quartzite (primarily Silicon Dioxide, SiO2)
Obsidian (Apache Tear)
Obsidian / Amorphous Volcanic Glass (main component: SiO2)
Sandstone (Quartzose type)
Arenite (primarily SiO2)
Sandstone (Greywacke)
Clastic Sedimentary Rock (SiO2 with lithic fragments)
Pyrite
Iron Sulfide (FeS2)
Dyed Quartz (often sold as 'Blue Quartz' or 'Blue Agate')
Silicon Dioxide (SiO2) with artificial pigment
Quartz / Rock Crystal
Silicon Dioxide (SiO2)
Rainbow Hematite (Titanium Coated)
Iron(III) oxide (Fe2O3) with Titanium/Metal Oxide coating
Orange Calcite
Calcium Carbonate (CaCO3)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
Chalcedony (Common Agate pebble)
Silicon Dioxide (SiO2)
Quartz Veined Basalt Pebble
Amygdaloidal Basalt with Quartz (SiO2) veining
Jasper containing epidote (Unakite-like)
Epidotized Jasper (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))