Black Spinel
Magnesium Aluminum Oxide (MgAl2O4)
Category
Browse mineral (chalcedony variety) specimens identified by the Rock Identifier community.
Black Spinel
Magnesium Aluminum Oxide (MgAl2O4)
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)
Larimar and Fossil Coral
Pectolite (NaCa2Si3O8(OH)) and Hexagonaria/Petoskey Stone
Vesicular Basalt (River Pebble)
Vesicular Basalt
Amethyst (Chevron or Banded variety)
Silicon Dioxide (SiO2) with iron impurities
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)
Quartz (in a rock matrix)
Quartz (SiO2)
Citrine
Quartz (SiO₂)
Jasper Conglomerate
Jasper Conglomerate (SiO2 matrix with varying mineral inclusions)
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.
Puddingstone
Conglomerate
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)
Quartz (Smoky/Grey Variety)
Silicon Dioxide (SiO2)
Orthoclase Feldspar (Sunstone variety)
KAlSi3O8 (Potassium Aluminum Silicate)
Quartz (Drusy/Crystalline variety)
Silicon Dioxide (SiO2)
Quartz (Orangey-white variety)
Silicon Dioxide (SiO2)
Banded Agate (Onyx Variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartz (Peach/Orange variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Yellowish variety)
Silicon Dioxide (SiO2)
Quartz (Milky or Clear variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Amethyst (Chevron or Banded variety)
Silicon Dioxide with Iron impurities (SiO2)
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Amber (Dark/Black Variety)
Succinite (Resinite), C10H16O
Quartz (Smoky/Grey variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Yellowish variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Crystal variety)
Silicon Dioxide (SiO2)