Chert (specifically Flint or Gray Chalcedony)
Microcrystalline Quartz (SiO2)
Category
Browse sedimentary (secondary mineral) within igneous specimens identified by the Rock Identifier community.
Chert (specifically Flint or Gray Chalcedony)
Microcrystalline Quartz (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Garnet (likely Pyrope or Almandine)
Garnet Group (complex nesosilicate minerals, e.g., Pyrope Mg3Al2(SiO4)3, Almandine Fe3Al2(SiO4)3, Spessartine Mn3Al2(SiO4)3, Grossular Ca3Al2(SiO4)3, Andradite Ca3Fe2(SiO4)3, Uvarovite Ca3Cr2(SiO4)3). The vivid red color in the image strongly suggests Pyrope or Almandine.
Quartz (Rose or Milky variety fragment)
Silicon Dioxide (SiO2)
Red Jasper (possibly Agatized Jasper)
Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)
Smoky Quartz
Smoky Quartz (SiO ₂)
Orange Calcite (Dogtooth/Cluster)
Calcium Carbonate (CaCO3)
Septarian Nodule (Dragon Stone)
Septarian Geode (CaCO3 + Mg + Fe)
Graphite
Graphite (Chemical Formula: C)
Scoria (Volcanic Rock)
Scoria (often basaltic scoria)
Smoky Quartz
Quartz (SiO₂)
Gneiss (River Cobble)
Gneiss (Foliated Metamorphic Rock)
Fluorite
Calcium Fluoride (CaF2)
Milky Quartz
Silicon dioxide (SiO2)
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gold
Native Gold (Au)
Gold Nugget
Native Gold (Au)
Ruby
Corundum (Al2O3 with Chromium impurities)
Gold
Native Gold (Au)
Dyed Agate
Silicon Dioxide (SiO2) with synthetic dyes
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Granite
Granite (Felsic intrusive igneous rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Gold
Native Gold (Au)
Agate (Bead Form)
Agate (Cryptocrystalline Quartz, SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Chert (Chert Nodule)
Microcrystalline quartz (SiO2)
Rose Quartz
Rose Quartz (SiO2)
Quartz
Silicon Dioxide (SiO₂)
Moqui Marble (Concretion)
Iron Oxide Concretion (Hematite-cemented Sandstone)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and mineral impurities
Hematite
Iron(III) oxide (Fe2O3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Sodalite (blue beads) and Clear Quartz (clear beads)
Sodalite: Na4Al3Si3O12Cl; Quartz: SiO2
Caliche (with Lichen Cover)
Calcium carbonate-cemented soil layer (CaCO3)
Wonderstone (Liesegang Sandstone)
Silicified Sandstone with Liesegang Rings (SiO2 + FeO(OH))
Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3(OH)4)