Selenite
Gypsum (CaSO4·2H2O), specifically the crystalline variety Selenite
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Selenite
Gypsum (CaSO4·2H2O), specifically the crystalline variety Selenite
Green Calcite
Calcite (CaCO3)
Fossilized Wood (Petrified Wood)
Silicified Wood (primarily quartz/chalcedony replacing organic matter)
Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)
Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates
Quartz
Quartz (SiO2 - Silicon Dioxide)
Botryoidal Chalcedony with Calcite
Chalcedony (SiO2 with accessory minerals, likely CaCO3)
Jasper (likely a variety of Brecciated Jasper or a patterned variety)
Silicon dioxide (SiO2)
Fancy Jasper
Chalcedony (cryptocrystalline quartz) with inclusions
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Pyrite (or Fool's Gold)
Pyrite (FeS₂)
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Chalcedony (Banded/Mottled Variety)
Chalcedony (a cryptocrystalline variety of Quartz, SiO2)
Quartz (possibly milky quartz or quartz with inclusions)
SiO2 (Silicon Dioxide)
Weathered Quartzite or Chert Pebble
Silicon Dioxide (SiO2)
River Pebble (Likely Quartzite or Chert)
Silicon Dioxide (SiO2)
River Cobble (likely Quartzite or Limestone)
SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)
Quartz
Silicon Dioxide (SiO2)
Red Jasper
Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)
Tiger's Eye and Carnelian Quartz
Silicon Dioxide (SiO2)
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz / Quartzite Fragment
Silicon Dioxide (SiO2)
River Pebbles (Sandstone and Quartzite)
SiO2 (Quartz) dominated clastic rocks
River Pebble (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) mixture with varied clastic minerals
River Pebble (likely Quartzite or Chert)
Silicon Dioxide (SiO2) crystal conglomerate
Quartzite and Chert
Silicon Dioxide (SiO2)
Hematite (beads)
Hematite (Fe₂O₃)
Quartz
Silicon Dioxide (SiO₂)
Quartz Pebble
Silicon Dioxide (SiO2)
Calcite
Calcite (CaCO₃)
Quartz Geode/Cluster
Quartz (SiO2)
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Banded Agate (likely Carnelian Agate or Sardonyx)
Agate is a common name for a microcrystalline variety of Quartz (SiO₂), specifically a form of Chalcedony.
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
Ruby
Corundum (Al₂O₃) with Chromium (Cr)
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Quartz
Quartz (SiO₂)
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles
Mixed gemstones (primarily Silicon Dioxide - SiO2)
Pyrite
Iron Pyrite (FeS2)