sedimentary
Pebble with Basaltic and Quartz-rich Banding
Polymictic Lithic Pebble
Hardness varies between 6 and 7 (due to quartz/silica content), color is primarily tan/beige with dark grey to black spots and a distinct dark band, luster is dull to waxy, cryptocrystalline structure.
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Physical properties
Hardness varies between 6 and 7 (due to quartz/silica content), color is primarily tan/beige with dark grey to black spots and a distinct dark band, luster is dull to waxy, cryptocrystalline structure.
Formation & geological history
Formed through sedimentary deposition, weathering, and fluvial or marine transport where various mineral fragments and rock types were cemented together, subsequently rounded by water action over millions of years.
Uses & applications
Used primarily as an ornamental specimen, in landscaping, or as a decorative stone for collectors.
Geological facts
Water-worn pebbles like this often reveal contrasting internal mineral compositions and inclusions that tell a complex geological story of erosion and transport.
Field identification & locations
Found commonly in riverbeds, beaches, and glacial outwash deposits. Identified by its smooth, rounded shape and contrasting dark inclusions within a lighter matrix.
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