Basalt with Weathering Crust
Extrusive mafic volcanic rock
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Basalt with Weathering Crust
Extrusive mafic volcanic rock
Chert (variously Flint)
Chert (Microcrystalline or cryptocrystalline Quartz, SiO₂)
Clear Quartz
Silicon Dioxide (SiO2) / Rock Crystal
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Grey River Pebble (Likely Quartz-rich or Limestone)
Clastic Sedimentary Rock (typically SiO2 or CaCO3 based)
Quartzite
Quartzite (chiefly SiO2)
Quartz (specifically Milky or Clear Quartz)
Silicon Dioxide (SiO2)
Septarian Nodule (Septarian Dragon Stone)
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)
Quartz Veined Siltstone or Graywacke
Clastic Sedimentary Rock with Quartz (SiO2) veining
Banded Agate (specifically Moss Agate or Plume Agate variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
Smoky Quartz
SiO2 (Silicon Dioxide)
Gneiss
Gneiss (High-grade metamorphic rock)
Yellow Quartz (Citrinated Quartz)
Silicon Dioxide (SiO2)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 primary composition)
Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
Chert (Nodule)
Chert (primarily Microcrystalline Quartz - SiO2)
Picture Jasper (specifically Biggs or Deschutes variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Gossan (Limonite/Goethite)
Hydrated iron oxides (primarily FeO(OH)·nH2O)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Ruby
Corundum (Al2O3 with Chromium impurities)
Amber (Copal)
Fossilized Tree Resin (C10H16O)
Basalt
Basalt (Igneous Volcanic Rock)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert (River Pebble)
Chert (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (with Quartz veins)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline silica (SiO2)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Chert (Limestone-based)
Silicon Dioxide (SiO2)
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxide
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartz Mineral
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)