Basalt
Basalt
Category
Browse mineral like byproduct (often mistaken for igneous rock or meteorite) specimens identified by the Rock Identifier community.
Basalt
Basalt
Clear Quartz (or Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Greenschist with Quartz Veining
Greenschist (commonly containing Chlorite, Actinolite, and Epidote)
Diorite
Diorite
Gold Nugget
Native Gold (Au)
Quartz
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Obsidian Arrowhead
Volcanic Glass (Amorphous Silicon Dioxide)
Greenstone / Greenschist
Greenschist (composed of Chlorite, Epidote, and Actinolite)
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
Sandstone (specifically Banded Sandstone)
Clastic sedimentary rock (primarily SiO2)
Quartz with Muscovite Mica
SiO2 with KAl2(AlSi3O10)(OH)2
Basalt
Basalt (Mafic volcanic rock)
Dalmatian Jasper
Aplite with Arfvedsonite inclusions
Granite
Granite (Phaneritic Quartz-Feldspar rock)
Eroded Brick or Pumice-like Scoria
Vesicular Basalt / Scoria (Anthropogenic variant: Eroded Firebrick)
Granite
Felsic intrusive igneous rock
Kaolinite (Kaolin)
Kaolinite (Al2Si2O5(OH)4)
Quartz
Silicon Dioxide (SiO2)
Sandstone
Clastic Sedimentary Rock
Dalmatian Stone (commonly Dyed)
Dalmatian Jasper (Peralkaline igneous rock)
Serpentine
Serpentine Group (primarily Antigorite or Lizardite), Mg3Si2O5(OH)4
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
Granite
Granite
Basalt with Epidote/Chlorite
Amygdaloidal Basalt (SiO2 with (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)))
Porphyritic Basalt (likely artificially dyed or altered)
Basalt with plagioclase phenocrysts (likely treated)
Chert (Nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Yellow Quartz
Silicon Dioxide (SiO2)
Milky Quartz Pebble with Iron Inclusions
Silicon Dioxide (SiO2)
Sugilite
Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Basalt
Extrusive mafic volcanic rock
Opalite
Man-made synthetic glass with opalescent effects (SiO2 + metal oxides)
Diorite
Intermediate plutonic igneous rock
Quartz (Milky / Clear Quartz Fragment)
Silicon Dioxide (SiO2)
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
Diorite with Quartz Veins
Diorite
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
Granite
Granite (Felsic Intrusive Igneous Rock)
Sandstone
Arenite