Diabase
Diabase (also known as Dolerite)
igneous
Category
Sedimentary Rock (Specifically A Concretion Or Possibly A Geode)
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Sandstone (with possibly iron oxides and other minerals)
Sandstone
Sedimentary rock
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (Mafic volcanic rock)
igneous
Quartz
Silicon Dioxide (SiO₂)
Mineral
Quartz Veined Rock (Likely Graywacke or Quartzite)
Silicon Dioxide (SiO2) veins in Metasedimentary matrix
metamorphic
Black Chert
Chert (microcrystalline quartz)
Mineral
Basalt (Vesicular)
Extrusive mafic igneous rock; primarily (Ca, Na)(Mg, Fe, Al)(Si, Al)2O6 with (Ca, Na)(Al, Si)4O8
igneous
Quartz
Silicon Dioxide (SiO₂)
Mineral
Limestone (specifically Dolomitic/Crystalline Limestone)
Sedimentary Carbonate Rock (CaCO3 / CaMg(CO3)2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Celestite (Celestine)
Strontium Sulfate (SrSO4)
mineral
Celestine (or Celestite)
Strontium sulfate (SrSO4)
mineral
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Mineral
Basalt (Vesicular)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Ocean Jasper
Silicon Dioxide (SiO2)
Mineral_variety_of_Chalcedony
Quartz Druzy Geode
Silicon Dioxide (SiO2)
mineral
Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)
Cryptocrystalline Quartz (SiO2) with inclusions
sedimentary
Quartz Geode (River Cobble)
Silicon Dioxide (SiO2)
mineral
Blue Chalcedony
Chalcedony (SiO2)
mineral
Celestite (Celectine)
Strontium sulfate (SrSO4)
mineral
Quartz Geode (with possible Manganese or Goethite coating)
Silicon Dioxide (SiO2)
mineral
Basalt Porphyry
Porphyritic Basalt
igneous
Chalcedony (Agate)
Silicon Dioxide (SiO2)
mineral
Sandstone (specifically Banded Sandstone)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Basalt (Greenstone)
Amygdaloidal Basalt / Chloritized Basalt
Igneous
Jasper with Quartz inclusion
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Stromatolite
Laminated biogenic sedimentary structure (formed by Cyanobacteria)
sedimentary
River Cobble (Basaltic/Andesitic)
Mafic Igneous Porphyritic Rock
igneous
Ironstone Concretion (Moqui Marble)
Iron Oxide Concretion (Fe2O3 / FeO(OH) mixed with SiO2)
sedimentary
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Marble
Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)
metamorphic
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
mineral
Sandstone Concretion
Sedimentary Concretion (SiO2 or CaCO3 cemented)
sedimentary
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (Mafic volcanic rock)
igneous
Druzy Quartz (on Chalcedony/Agate base)
Silicon Dioxide (SiO2)
mineral
Diorite (possibly fine-grained variety or a related intermediate intrusive rock like a felsic gabbro or a dark granodiorite)
Diorite (Igneous rock, intrusive, intermediate composition)
Igneous Rock
Hag Stone
Perforated Sedimentary Rock (typically Limestone or Sandstone)
sedimentary
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Milky Quartz
Quartz (Silica / Silicon Dioxide), SiO2
mineral