Limestone (specifically Fossiliferous Limestone)
Calcium Carbonate (CaCO3)
sedimentary
Category
Mineral, Specifically A Rock Fragment
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Learn about Mineral, Specifically A Rock Fragment in the encyclopedia
View all →
Basalt (Road Gravel)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Quartz (Quartzite fragment)
Silicon Dioxide (SiO2)
mineral
Unidentified tan rock fragment
Likely limestone or calcareous sandstone; exact identification requires testing
sedimentary
Milky Quartz with Matrix
Silicon Dioxide (SiO2)
mineral
Sandstone and Mixed Rock Assemblage
Clastic Sedimentary Rock / Quartz Arenite
sedimentary
Quartz (Clear / Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Chert (Flint Nobule)
Silicon Dioxide (SiO2)
sedimentary
Pebble
Lithified rock fragment / Sedimentary clast
sedimentary
Granite
Intrusive Igneous Rock
igneous
Serpentine
(Mg,Fe)3Si2O5(OH)4
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Mineral, specifically a detrital grain
Likely quartz-rich rock or weathered granite fragment
Granite-like quartz–feldspar aggregate; exact identification requires testing
igneous
Light-colored weathered stone, possibly limestone or quartz-rich rock
Indeterminate; likely calcitic limestone (mostly CaCO₃) or quartz sandstone (SiO₂)
sedimentary
Sandstone
Sedimentary Rock (Quartz arenite or arkose)
sedimentary
Green Aventurine
Silicon Dioxide (Quartz) with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
metamorphic
Sandstone
Arenite (Clastic Sedimentary Rock)
sedimentary
Foliated metamorphic rock, likely slate or phyllite
Fine-grained metapelite; commonly quartz–mica–chlorite with possible graphite
metamorphic
Red jasper
Jasper (microcrystalline quartz, SiO₂), iron-oxide-rich variety
mineral
Fossiliferous Limestone (Chert/Clay mixed)
Calcium Carbonate (CaCO3) / Silicon Dioxide (SiO2)
sedimentary
Red Sandstone Pebble
Quartzose Sandstone
sedimentary
Granite fragment
Phaneritic Igneous Rock (Granitic composition)
igneous
Breccia
Sedimentary Breccia
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Grey Pebble (Sandstone / Quartzite Pebble)
Sedimentary rock (primarily Quartz - SiO2)
sedimentary
Sandstone
Arenite
sedimentary
Greenstone Porphyry
Porphyritic Metavolcanic Rock
igneous
Gneiss
Gneiss (High-grade Regional Metamorphism)
metamorphic
Breccia
Clastic Breccia
sedimentary
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
sedimentary (chemical/biological origin)
Greenstone
Greenschist (metamorphosed mafic igneous rock)
metamorphic
Likely weathered granite or granitic gneiss fragment
Granite: quartz + feldspar + mica; possibly gneiss if foliation is confirmed
igneous
Asphalt Chunk
Asphalt concrete
man-made composite
Bumblebee Jasper
Calcite-Auripigment-Pyrite-Realgar assemblage (Carbonate/Sulphide mixture)
mineral
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Mineral
Sandstone with Iron Staining
Arenite (SiO2 with Fe2O3)
sedimentary
Limonite (with Goethite/Hematite glaze)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Sandstone (with potential Concretion or Fossil fragment)
Arenite (primarily SiO2)
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and organic impurities
sedimentary
Sandstone (lithic wacke/conglomerate mix)
Clastic Sedimentary Rock (SiO2 with lithic fragments)
sedimentary
Chert (Nodule / Geode fragment)
Microcrystalline Quartz (SiO2)
sedimentary