igneous, sedimentary, and metamorphic

Drill Core Samples (Varied Lithology)

Multi-lithological core samples (containing potential granite, marble, and phyllite/schist sequence)

Hardness: 3-7 Mohs (variable); Color: grey, green, mottled white, and dark charcoal; Luster: dull to vitreous; Crystal structure: massive to foliated (fine-grained matrix with mineral veining); Cleavage: present in metamorphic sections; Specific gravity: approx. 2.6-3.0.

Hardness: 3-7 Mohs (variable)
Color: grey, green, mottled white, and dark charcoal
Luster: dull to vitreous

Identified March 16, 2026More igneous, sedimentary, and metamorphic →

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Physical properties

Formation & geological history

Extracted from the Earth via diamond core drilling. These represent a cross-section of the lithosphere, likely featuring contact metamorphism and hydrothermal veining from diverse geological ages (often Precambrian to Mesozoic depends on site).

Uses & applications

Geological exploration, mineral prospecting (gold, copper, or nickel), and site characterization for engineering and construction projects.

Geological facts

Geologists use 'RQD' (Rock Quality Designation) on these cylinders to determine the stability of the ground. The smooth cylindrical shape is achieved by a rotating hollow bit tipped with industrial diamonds.

Field identification & locations

Identify by cylindrical shape and varying mineral bands. Found at active mining sites or construction survey areas. Collectors should look for 'vugs' or mineral-rich veins within the cylinders.

Other igneous, sedimentary, and metamorphic specimens

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River Pebbles and Quartz

Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)

mixed

Zoisite with Ruby (Anyolite)

Zoisite – Ca2Al3(SiO4)3(OH) with inclusions of Ruby (Al2O3:Cr)

metamorphic

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

mineral

Pyrite

Iron Sulfide (FeS2)

mineral

Pyrite in Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

mineral

Quartz (Raw Chunk)

Silicon Dioxide (SiO2)

mineral