Sandstone (Ferruginous/Red Sandstone)
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
Category
Browse mineral (variety of chalcedony) specimens identified by the Rock Identifier community.
Sandstone (Ferruginous/Red Sandstone)
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
Obsidian
Amorphous volcanic glass (primarily SiO2)
Garnet
Garnet Group (complex nesosilicates with general formula X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+, V3+)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Smoky Quartz
SiO2 (Silicon Dioxide)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 + varied clasts)
Sandstone (Red/Brown Variety)
Arenite (SiO2 with iron oxide impurities)
Quartz
Quartz (SiO₂)
Quartz
Quartz (SiO₂)
Black Spinel
Magnesium Aluminum Oxide (MgAl2O4)
Sandstone
Arenite (composed primarily of SiO2)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(OH)₄(BO₃)₃Si₆O₁₈)
Gastly (Trick or Trade Halloween Series)
Cellulose-carbonaceous composite (Lignocellulose laminated with pigmentary polymers)
Jasper Breccia
Silicon Dioxide (SiO2) with impurities
Orthoclase Feldspar
Potassium Feldspar (KAlSi3O8)
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Basalt
Basalt (Mafic Extrusive)
Quartz (Milky or Grainy Variety)
Silicon Dioxide (SiO2)
Orthoclase (Potassium Feldspar)
KAlSi3O8 (Potassium Aluminum Silicate)
Yellow Quartz (Citrine Quartz or Yellow Chalcedony)
Silicon Dioxide (SiO2)
Hematite
Hematite (Fe2O3)
Obsidian
Obsidian (Volcanic Glass)
Vesicular Basalt (River Pebble)
Vesicular Basalt
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)
Larimar and Fossil Coral
Pectolite (NaCa2Si3O8(OH)) and Hexagonaria/Petoskey Stone
Amethyst (Chevron or Banded variety)
Silicon Dioxide (SiO2) with iron impurities
Quartz (in a rock matrix)
Quartz (SiO2)
Citrine
Quartz (SiO₂)
Jasper Conglomerate
Jasper Conglomerate (SiO2 matrix with varying mineral inclusions)
Puddingstone
Conglomerate
Amazonite (likely mixed with other feldspars/minerals)
Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.
Quartz (Milky and Smoky variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Cloudy Variety)
Silicon Dioxide (SiO2)
Quartz (Milky or Druzy variety)
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (SiO2 principal)
Amethyst (Pale/Lavender variety)
Silicon Dioxide (SiO2)
Quartz (Smoky/Milky Variety)
Silicon Dioxide (SiO2)
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
Quartz (Translucent/Rose variety)
Silicon Dioxide (SiO2)