Sandstone
Clastic sedimentary rock (primarily SiO2)
Category
Browse mineraloid like synthetic material specimens identified by the Rock Identifier community.
Sandstone
Clastic sedimentary rock (primarily SiO2)
Chalk
Carbonate rock (mainly CaCO3)
Porphyritic Andesite
Andesite (porphyritic variety)
Sandstone (likely Quartzose)
Arenite (primarily SiO2)
Amazonite
Microcline (K(AlSi3O8))
Milky Quartz (Water-worn pebble)
Quartz (Silicon Dioxide, SiO2)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Diorite (River Cobble)
Intrusive Igneous Diorite
Vesicular Basalt (Iron-rich)
Scoriaceous Basalt / Oxidized Vesicular Basalt
Sandstone (Ferruginous)
Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)
River Cobble (Quartzite and Iron-stained Quartz)
Quartzite (SiO2 with iron oxide impurities)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Basalt (River Pebble)
Basalt
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Red Jasper
Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)
Jasper
Silicon Dioxide (SiO2)
Granite
Granite (a common type of Felsic Intrusive Igneous Rock)
River Stone (River Pebbles)
Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)
Quartzite (River Cobble)
Metamorphosed Quartz Sandstone (SiO2)
Rough Diamond
Diamond (C)
Chert (or Flint)
Chert (microcrystalline or cryptocrystalline quartz, SiO2)
Aventurine
Aventurine Quartz (SiO2 with inclusions)
Quartzite Pebble
Quartzite (mostly SiO2)
Tiger's Eye (Multicolor/Variegated)
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxides)
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Yellow Jasper
Silicon Dioxide (SiO₂)
Fossil Shell (Bivalve)
Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) - variety of Chalcedony
Blue Lace Agate
Cryptocrystalline Quartz (SiO2) with trace minerals
Diamond (or Diamond Simulant)
Carbon (C) - Native Element
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
Moss Agate
Chalcedony (Silicon Dioxide - SiO2) with inclusions
Breccia
Breccia
Glazed Ceramic Tile
Fused Silicate-Clay composite
Diamond
Diamond (pure Carbon, C)
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
Jasper (Mookaite style)
Silicon Dioxide (SiO2) with iron and manganese inclusions
Quartz
Quartz (Silicon Dioxide, SiO2)
Diamond (set in jewelry)
Diamond (Carbon, C)