Polished red jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides
mineral
Category
Sedimentary (With Some Aspects Of Mineral Replacement)
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Learn about Sedimentary (With Some Aspects Of Mineral Replacement) in the encyclopedia
View all →
Sea Urchin Fossil
Echinoidea (test/fossil)
fossil
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
mineral
Vuggy Chert / Silicified Limestone
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
sedimentary
Tumbled brown jasper
Microcrystalline quartz (chalcedony), chiefly SiO₂, colored by iron oxides and other inclusions
mineral
Fossil bivalve shell in matrix
Likely fossilized oyster or mussel (Bivalvia), with a nacreous aragonite shell; exact genus and age require locality and preparation details
fossil
Gneiss
Gneiss (foliated metamorphic rock)
metamorphic
Fossil shark tooth
Likely fossilized shark tooth, possibly Otodus megalodon
fossil
Iron-stained chert or weathered ironstone nodule
Microcrystalline quartz (SiO₂), possibly limonite/goethite-bearing
sedimentary
Chert (specifically Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Favosites Fossil (Honeycomb Coral)
Favosites (Extinct genus of Tabulate Coral)
sedimentary
Sandstone
Arenite
sedimentary
Ironstone Concretion
Siderite or Hematite Concretion
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Tumbled yellow jasper (likely serpentine or calcite-rich stone)
Jasper: microcrystalline quartz (SiO₂); exact yellow veining may indicate serpentine, calcite, or iron oxides
mineral
Petrified Wood
Silicified wood (primarily SiO2)
sedimentary
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
mineral
Likely anthracite coal
Anthracite, a carbon-rich coal (predominantly elemental carbon)
sedimentary
Gneiss
Gneiss
metamorphic
Blue Celestite (with Galena)
Strontium sulfate (SrSO4) and Lead sulfide (PbS)
mineral
Petrified Bone (Fossil Bone)
Per mineralization fossil bone (varies by organism, predominantly replacement by SiO2 - Quartz/Chalcedony)
fossil
Polished Orbicular Jasper tower
Orbicular jasper (microcrystalline quartz/chalcedony with iron oxides and accessory minerals)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Sandstone (likely Graywacke or Siltstone variety)
Clastic Sedimentary Rock (SiO2 with assorted mineral fragments)
sedimentary
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Fossil gastropod in granite-like stone
Gastropoda indet.; enclosing rock likely polished granite or gneiss
fossil
Chert Nodule
Microcrystalline Quartz (SiO2)
sedimentary
Fossilized bone fragment, possibly mammalian long bone
Mineralized bone (commonly apatite, Ca₅(PO₄)₃(OH,F,Cl), replacing original bone)
fossil
Gneiss
Gneiss
metamorphic
Flint
Sedimentary cryptocrystalline quartz (SiO2)
sedimentary
Chert (Green Chert or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Shark Teeth
Carcharhiniformes or Lamniformes species (common mineral: Fluorapatite/Ca5(PO4)3F)
sedimentary (fossilized organic matter)
Red Jasper (Chalcedony)
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Chert (Jasper)
Microcrystalline Quartz (SiO2) with iron oxide inclusions
sedimentary
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Petrified Wood
Silicified Wood / Fossilized Wood (SiO2)
sedimentary
Dalmatian Stone
Peralkaline rhyolite with arfvedsonite (formerly incorrectly called Dalmatian Jasper)
igneous
Gneiss
Gneiss
metamorphic
Mixed collection of polished pebbles, including probable fossiliferous limestone
Unidentified sedimentary rocks; the gray pebble with circular fossils may be bioclastic limestone
sedimentary
Amber
Succinicum (C10H16O)
mineral
Quartz-rich rock fragment, possibly chert or weathered quartz
Microcrystalline quartz (SiO₂), tentative identification
mineral