Rock Identifier
Tumbled brown stone, likely basalt or iron-stained quartzite (Indeterminate from photograph; possible basalt (mafic silicate rock) or quartzite (SiO₂)) — igneous or metamorphic
igneous or metamorphic

Tumbled brown stone, likely basalt or iron-stained quartzite

Indeterminate from photograph; possible basalt (mafic silicate rock) or quartzite (SiO₂)

AI-generated identification · may be incorrect

Dark brown, rounded and polished/weathered, with dull to slightly granular luster and scattered pale mineral grains; hardness is likely ~5.5–7 Mohs, but texture and cleavage are not diagnostic visually.

Identified More igneous or metamorphic →
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Physical properties

Dark brown, rounded and polished/weathered, with dull to slightly granular luster and scattered pale mineral grains; hardness is likely ~5.5–7 Mohs, but texture and cleavage are not diagnostic visually.

Formation & geological history

The rounded shape indicates stream abrasion or tumbling; basalt forms from cooled lava, whereas quartzite forms when sandstone is metamorphosed. Age and locality cannot be determined from the image.

Uses & applications

Common material for landscaping, educational specimens, lapidary work, and inexpensive polished stones; unlikely to have significant jewelry value without confirmed composition.

Geological facts

The small pale flecks may be feldspar, quartz, or weathered alteration minerals; a darker brown surface can result from iron-oxide staining or weathering.

Field identification & locations

Test hardness against glass, inspect a fresh break, and use a magnet, streak, acid, and specific-gravity tests; definitive identification requires these tests or microscopy. Similar stones occur widely in river gravels and glacial deposits.

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fossil
Fossilized marine shell fragment (Likely a bivalve or gastropod shell preserved as calcite (CaCO₃)) — fossil

Fossilized marine shell fragment

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mineral
Fossiliferous limestone fragment (Calcitic limestone; mainly calcium carbonate (CaCO₃), possibly with shell or coral debris) — sedimentary

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sedimentary
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Granite with Epidote

Granite, containing quartz, feldspar, and epidote

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Fossilized bivalve shell or shell-rich limestone (Likely an indeterminate fossil mollusk; calcite/aragonite (CaCO₃), possibly preserved in limestone) — fossil

Fossilized bivalve shell or shell-rich limestone

Likely an indeterminate fossil mollusk; calcite/aragonite (CaCO₃), possibly preserved in limestone

fossil