sedimentary
Conglomerate
Clastic Sedimentary Conglomerate (SiO2 based clasts in matrix)
Hardness: 6.5-7 (for quartz clasts), Color: Tan/gray matrix with brown and dark gray clasts, Luster: Dull/Earthy matrix with waxy clasts, Structure: Clastic with rounded grains, Specific Gravity: 2.6-2.8
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 (for quartz clasts), Color: Tan/gray matrix with brown and dark gray clasts, Luster: Dull/Earthy matrix with waxy clasts, Structure: Clastic with rounded grains, Specific Gravity: 2.6-2.8
Formation & geological history
Formed by the lithification of rounded gravel and pebbles, typically in high-energy environments like river beds or alluvial fans where water rounds the stones over time.
Uses & applications
Used primarily in the construction industry as coarse aggregate, as a decorative stone in landscaping, and occasionally as an ornamental building material.
Geological facts
Conglomerates are known as 'pudding stones' when they contain distinct, colorful clasts. They are one of the best indicators of ancient river systems and fast-flowing water in the geologic record.
Field identification & locations
Identify by the presence of rounded pebbles (clasts) larger than 2mm cemented together. Found in sedimentary basins, old river channels, and coastal areas.
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