Metamorphic (Likely Gneiss or Schist based on texture)

Drill Core Sample

Cylindrical Rock Core (Specific mineralogy varies by extraction site)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs scale), Color: Mottled gray and green with dark patches, Luster: Dull/Earthy, Crystal Structure: Foliated or crystalline, Cleavage: Non-cleavage in cylinder form, Specific Gravity: 2.6-3.0.

Identified March 30, 2026More metamorphic (likely gneiss or schist based on texture) →

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Physical properties

Formation & geological history

Artificial extraction from subsurface formations. This core was produced by a hollow diamond-tipped drill bit during mineral exploration or geotechnical engineering. The geological age depends on the strata of the collection site.

Uses & applications

Used for geological mapping, mineral exploration analysis (identifying ore bodies), and geotechnical site investigations for construction projects.

Geological facts

Geologists use 'core logging' to describe the sequence of rocks found underground. These samples are the primary source of 'ground truth' for what exists deep beneath the Earth's surface.

Field identification & locations

Identify in the field by its perfectly cylindrical shape with smooth sides and rough ends. Often found near active mining sites, oil exploration rigs, or major highway/bridge construction sites.