igneous

Orbicular Rhyolite (Rainforest Jasper)

Rhyolite containing Spherulites (SiO2 with impurities)

Hardness: 6.5–7 on Mohs scale; Color: Cream, tan, and green groundmass with dark grey or blue orbicular patches; Luster: Dull to waxy; Texture: Fine-grained with rounded inclusions; Cleavage: None.

Hardness: 6
Luster: Dull to waxy

Identified March 24, 2026More igneous →

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Physical properties

Hardness: 6.5–7 on Mohs scale; Color: Cream, tan, and green groundmass with dark grey or blue orbicular patches; Luster: Dull to waxy; Texture: Fine-grained with rounded inclusions; Cleavage: None.

Formation & geological history

Formed from rapid cooling of silica-rich volcanic lava where bubbles or seeds allow minerals to crystallize in radial, spherical patterns called spherulites. These deposits are typically associated with volcanic activity from the Cenozoic era.

Uses & applications

Primarily used for ornamental purposes, including stone carvings, cabochons for jewelry, and as decorative pocket stones for collectors.

Geological facts

Also known as 'Rainforest Jasper' despite not being a true jasper (which is sedimentary). The circular 'eyes' or 'orbs' are actually clusters of radiating crystal needles, usually quartz or feldspar.

Field identification & locations

Identify by looking for distinct orb-like or circular patterns within a fine-grained volcanic matrix. Commonly found in Western Australia and parts of the United States like Oregon. Collectors should look for high contrast between the orbs and the background rock.

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Fluorapatite (Ca5(PO4)3F)

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Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Igneous

Magnetite

Iron(II,III) oxide (Fe3O4)

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Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

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Blue Apatite

Apatite (Group), Ca5(PO4)3(F,Cl,OH)

mineral

Magnetite

Magnetite (Fe3O4)

mineral