Gneiss
High-grade metamorphic rock (Gneiss)
Category
Browse mineral like byproduct (technogenic) specimens identified by the Rock Identifier community.
Gneiss
High-grade metamorphic rock (Gneiss)
Obsidian
Obsidian (Amorphous volcanic glass, SiO2 rich)
Chalcedony (specifically Agate or Moonstone-like Quartz)
Silicon Dioxide (SiO2)
Geode (unopened nodule)
Silicon Dioxide (SiO2) Nodule
Sandstone
Arenite (Siliclastic sedimentary rock), SiO2 + various minerals
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
Vesicular Basalt with Epidote
Vesicular Basalt (Mg, Fe)2SiO4 with Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
Orbicular Granite
Orbicular Granitoid
Sandstone (Ferruginous)
Arenite (with Iron Oxides)
Basalt with Quartz/Calcite Veins
Basalt (Aphanitic Mafic Igneous Rock)
Fossilized Coral (Petoskey Stone type)
Hexagonaria percarinata (Fossilized Rugose Coral)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay impurities
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Geode (unopened) or Calcareous Nodule
Siliceous or Calcareous Concretion/Nodule
Obsidian
Volcanic glass
Vesicular Basalt (commonly mistaken for Slag)
Scoriaceous Basalt (composed primarily of Plagioclase Feldspar and Pyroxene)
Quartz (Chert/Chalcedony variety)
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Basalt with Epidote (Greenstone)
Amygdaloidal Basalt (Ca2(Al, Fe)3(SiO4)3(OH) inclusions)
Basalt-Amugydule (Amygdaloidal Basalt)
Aphanitic Mafic Igneous Rock with Vesicle Infillings
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
Aragonite (Botryoidal/Coralloidal variety)
Aragonite (CaCO3)
Astrophyllite
Astrophyllite (K2NaFe7Ti2Si8O26(OH)4F)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Blue Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Basalt with Amygdules
Amygdaloidal Basalt
Jasper (River pebble)
Jasper / Silicon Dioxide (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Quartz
Quartz (SiO₂)
Goethite (Iron Ore)
Goethite (FeO(OH))
Quartz Mineral
Silicon Dioxide (SiO2)
Lepidolite with Quartz
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Greenschist with Quartz Veining
Greenschist (commonly containing Chlorite, Actinolite, and Epidote)
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8
Black Obsidian with white veins
Volcanic Glass (70–75% SiO2)
Schist
Mica Schist (primarily Muscovite and Quartz)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)