Basalt — Basalt
Basalt Burkhard Mücke, Wikimedia Commons, CC BY SA 4.0

Material · lithic

Basalt

North America — Southwest, North America — Great Basin & Plateau, Mesoamerica, Near East & Mesopotamia

Basalt is the dark volcanic rock used for ground-stone axes, manos and metates, and for chipped tools in the Southwest, Great Basin, Mesoamerica and the Near East, where Natufian mortars and Olmec colossal heads are basalt. Southwestern three-quarter-grooved axes are often basalt. It is heavy and durable.

Kindlithic
RegionsNorth America — Southwest, North America — Great Basin & Plateau, Mesoamerica, Near East & Mesopotamia

Sources

Basalt flows cover large parts of the Southwest, the Columbia Plateau, the Great Basin, central Mexico, the Golan and the Levantine Hauran, and Ethiopia; tools were made from cobbles and outcrops. Tool-quality basalt was selected for fine grain and freedom from vesicles.

Identification

Basalt is dark grey to black, fine-grained, sometimes vesicular, with a dull surface and a rough fracture; it takes a smooth polish when ground. Weathering produces a brown or grey rind. It is distinguished from greenstone by colour and from diorite by grain.

Substitutes and fakes

Basalt ground-stone is reproduced in Mexico and the Near East on power tools; genuine pieces show pecking under the polish and use wear. Aztec-style basalt sculpture is a major forgery category.

Elsewhere

Cite this article

Stratum Study. "Basalt" (Material). Stratum Study pack 2026.09, as of 2026-09-21. https://stratum.black/study/materials/basalt. Accessed 2026-09-21.

@misc{stratum-basalt,
  title        = {Basalt},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/materials/basalt}},
  year         = {2026},
  note         = {Material article, Stratum Study pack 2026.09, as of 2026-09-21; sources: stratum, wikidata, commons. Accessed 2026-09-21.}
}

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Sources for this article: Stratum editorial (Stratum editorial);Wikidata (CC0);Wikimedia Commons (CC-BY-4.0). As of 2026-09-21; Study pack 2026.09. Data reproduced under the licences shown; text in Stratum's own words unless a section names its source.

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