Uncertain

Browse uncertain specimens identified by the Rock Identifier community.

Tumbled brown stone, likely tiger’s-eye or jasper

Quartz-rich microcrystalline silica, likely SiO₂ (possible tiger’s-eye; identification uncertain from image)

mineral

Orbicular granite (likely larvikite or related granitic rock)

Granite composed mainly of quartz, feldspar, and dark mafic minerals; exact variety is uncertain from the image

igneous

Likely tumbled amber or orange chalcedony

Uncertain from image; possibly amber (fossilized resin, chiefly C10H16O) or carnelian (microcrystalline quartz, SiO₂)

gemstone

Tumbled dark red-brown stone, possibly jasper

Likely opaque microcrystalline quartz (chalcedony/jasper), SiO₂; exact identification is uncertain from the blurred photograph

gemstone

Rounded dark pebble, likely basaltic andesite

Fine-grained mafic volcanic rock; probable basalt or andesite, identification uncertain from image alone

igneous

Polished orbicular/porphyritic granite or breccia

Likely potassium-feldspar–quartz granite with amphibole/biotite and epidote; exact variety uncertain from the image

igneous

Polished/tumbled multicolored stone, possibly jasper

Likely opaque microcrystalline quartz (chalcedony/jasper); exact identification is uncertain because the image is out of focus

mineral

Weathered fossiliferous limestone fragment, possibly fossil coral or shell material

Indeterminate carbonate fossil in calcitic limestone; likely composed mainly of calcite (CaCO₃), but species identification is not possible from this image alone

fossil

Quartz-bearing iron-rich rock, possibly quartzite or hydrothermal breccia

Quartz (SiO₂) with iron oxides/hydroxides, likely limonite/goethite; exact host rock is uncertain from the photograph

metamorphic

Pink quartz bead necklace/strand

Quartz, silicon dioxide (SiO₂), likely rose quartz or pink chalcedony; exact identification is uncertain from the image

gemstone

Yellow tumbled/rough chalcedony, possibly citrine or dyed agate

Chalcedony (microcrystalline SiO₂), with yellow coloration likely from iron oxides; exact identification is uncertain from the photograph

mineral

Tumbled or rough turquoise-like specimen

Turquoise, hydrated copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O; identification is uncertain from the image

mineral

Weathered pegmatite or feldspar-rich granite fragment

Granitic pegmatite, composed mainly of potassium feldspar and quartz, with minor mica; exact identification is uncertain from the photograph

igneous

Weathered, iron-stained quartz-rich pebble (uncertain identification)

Microcrystalline quartz, SiO₂, with iron-oxide/hydroxide staining and dark matrix inclusions

mineral

Pale green tumbled mineral fragment, likely serpentine or green calcite

Probable serpentine-group mineral (Mg3Si2O5(OH)4) or, less likely, calcite (CaCO3); identification is uncertain from the photograph

mineral

Tumbled blue glassy mineral, possibly sodalite or blue aventurine

Identification uncertain; likely sodalite (Na₈Al₆Si₆O₂₄Cl₂) or blue-dyed quartz/slag-like material

mineral

Tumbled quartz-rich rock, possibly jasperized quartz or quartzite

Quartz (SiO₂), likely with iron-oxide staining and minor feldspar or other silicate minerals; exact identification is uncertain from the photograph

metamorphic

Dyed blue howlite (turquoise imitation), possibly dyed magnesite

Howlite: Ca₂B₅SiO₉(OH)₅; the vivid blue color is artificial dye. Exact identification is uncertain from the photograph alone.

gemstone

Weathered granite (feldspathic, iron-stained granite)

Granite; primarily quartz, potassium feldspar, plagioclase feldspar, and minor mica/amphibole. Exact identification is uncertain from a single photograph.

igneous

Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate

Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)

gemstone

Mixed rounded stream pebbles

Most appear to be granitic and mafic igneous rocks, including granite, gneiss, basalt, and possibly quartzite; exact identification is uncertain from the image.

igneous

Honey-colored chalcedony (possibly yellow/orange agate or carnelian)

Chalcedony, a microcrystalline variety of quartz; SiO₂. The color may result from iron-oxide inclusions. Exact identification is uncertain from a photograph alone.

gemstone

Basalt and weathered granite-like rock

Dark specimen: basalt, likely vesicular or fine-grained mafic volcanic rock; tan specimen: uncertain, possibly weathered granite or iron-stained felsic rock

igneous