Polished fossil shell fragment
Likely fossilized bivalve shell; mineralized aragonite/calcite (exact taxon indeterminate)
Category
Browse indeterminate specimens identified by the Rock Identifier community.
Polished fossil shell fragment
Likely fossilized bivalve shell; mineralized aragonite/calcite (exact taxon indeterminate)
Rounded weathered stone, likely quartz-rich sandstone or iron-stained quartzite
Indeterminate; probable quartz (SiO₂)-rich clastic rock with iron-oxide staining
Tumbled stone, likely ocean jasper or quartzite
Indeterminate from photograph; probable quartz-rich silicate rock, mainly SiO₂
Rounded weathered stone, likely sandstone or chert
Indeterminate; probable quartz-rich clastic rock (sandstone) or microcrystalline silica (chert)
Likely tumbled green mineral (possibly serpentine or aventurine)
Indeterminate; possibilities include serpentine-group minerals, nephrite, or green aventurine quartz
Weathered mineralized rock fragment
Indeterminate; likely quartz–feldspar-rich lithic material with iron-oxide staining
Possibly tumbled dark stone or mineral specimen
Indeterminate from image; possibly black tourmaline, basalt, or another dark silicate
Likely weathered quartz-rich rock or mineral fragment
Indeterminate from image; possibly quartz-bearing pegmatite or iron-stained quartz
Likely weathered igneous rock fragments
Indeterminate; possibly basaltic or granitic rock with quartz, feldspar, and dark mafic minerals
Unidentified dark mineral/rock fragment
Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral
Weathered igneous rock fragment, possibly granite or granitic gneiss
Indeterminate; likely quartz–feldspar–mica aggregate (granite), possibly foliated gneiss
Weathered brown stone, likely sandstone or mudstone
Indeterminate clastic sedimentary rock; likely quartz-rich sandstone or lithified mudstone
Fossil shell fragment, likely brachiopod or bivalve
Indeterminate fossilized marine mollusk or brachiopod; mineralized calcite shell in a carbonate matrix
Polished/tumbled quartz-rich pebble, possibly jasper or quartzite
Indeterminate; likely microcrystalline quartz (SiO₂), potentially iron-stained jasper or quartzite
Small rounded pebble, likely quartz-rich stone
Indeterminate from photograph; possibly microcrystalline quartz (SiO₂) or a weathered silicate pebble
Tumbled brown-and-white feldspar-rich stone, likely granite or quartzite
Indeterminate; probably quartz–feldspar aggregate (granite) or quartzite, with iron-oxide staining
Tumbled gray feldspar-rich stone, possibly granite or quartzite
Indeterminate; likely quartz–feldspar aggregate, potentially fine-grained granite or quartzite
Weathered quartz-rich rock, possibly sandstone or quartzite
Indeterminate; likely quartz sandstone (SiO₂-rich), possibly weakly metamorphosed quartzite
Weathered fossiliferous limestone or fossil fragment
Indeterminate bioclastic carbonate rock; likely calcite (CaCO₃) with fossil shell material
Weathered sandstone or siltstone boulder
Indeterminate clastic sedimentary rock, likely quartz-rich sandstone (SiO₂-dominant)
Dark beach-worn rock, possibly basalt with a greenish pebble
Indeterminate from photograph; likely basalt or another fine-grained volcanic rock
Likely weathered copper-bearing rock
Indeterminate from the photo; possibly malachite-bearing rock (Cu₂CO₃(OH)₂)
Unidentified small translucent mineral fragment
Indeterminate from the image; could be quartz (SiO₂) or another pale, translucent mineral
Possible tumbled dark-green stone
Indeterminate from the blurry image; possibly serpentine or another green ornamental stone
Fossilized coral (possible)
Indeterminate fossil; the image does not show enough diagnostic detail to identify a taxon
Probable weathered sandstone or iron-rich sedimentary rock
Indeterminate siliciclastic rock; likely quartz-rich sandstone with iron-oxide staining
Small rounded pebble, likely quartz-rich stone
Indeterminate; possibly quartzite or light-colored granitoid, composed mainly of quartz and feldspar
Unidentified small stone fragments
Indeterminate; the image does not show enough detail to identify a mineral or rock species
Tumbled brown feldspar-rich rock, possibly tiger’s-eye or brecciated quartz
Indeterminate from image; likely quartz (SiO₂) with iron-stained feldspar or amphibole
Fossil shell fragment
Indeterminate marine mollusk shell; likely calcitic or aragonitic shell material (CaCO₃)
Weathered quartz- or feldspar-rich rock fragment
Indeterminate light-colored silicate rock; possibly quartz or feldspar in a granitic fragment
Weathered fossiliferous limestone, likely coral or shell fragment
Calcite (CaCO₃), biogenic limestone; exact fossil taxon indeterminate from the image
Likely fossilized bone or tooth fragment
Indeterminate fossil bone; mineral replacement commonly calcite, silica, or iron oxides
Rounded river pebble, likely quartz-rich chert or fine-grained sandstone
Indeterminate lithic clast; possible microcrystalline quartz (chert) or quartz-rich sandstone
Tumbled brown stone, likely basalt or iron-stained quartzite
Indeterminate from photograph; possible basalt (mafic silicate rock) or quartzite (SiO₂)
Weathered iron-rich stone, possibly chert or quartzite
Indeterminate; likely silica-rich rock with iron-oxide staining (SiO₂-dominant)
Blue-gray mineral/rock fragment
Indeterminate; possibly azurite-bearing material, blue chalcedony, or dyed/coated stone
Yellow quartz-bearing rock, possibly sulfur-stained quartz or calcite
Indeterminate; likely quartz (SiO₂) and/or calcite (CaCO₃) with yellow iron/sulfur staining
Weathered sandstone or siltstone pebble
Indeterminate siliciclastic sedimentary rock, likely quartz-rich sandstone (SiO₂-dominated)
Fossilized tooth or jaw fragment (likely fish or reptile)
Indeterminate vertebrate bone/tooth; mineralized hydroxyapatite, commonly Ca₅(PO₄)₃(OH)
Polished metallic ore/mineral specimen, possibly pyrite-bearing schist
Indeterminate from image; likely pyrite (FeS₂) with quartz and/or mica in a metamorphic matrix
Weathered iron-rich rock, possibly ironstone or altered basalt
Indeterminate; likely ferruginous basalt/ironstone containing hematite-goethite and silicate minerals