In sedimentary rocks it occurs as detrital material.
When the rocks are concealed by detrital material he looks for outcroppings on steep hillsides, on the crests of hills or ridges, in the beds of streams, in landslides, in the roots of overturned trees, and in wells, quarries, roadcuttings and other excavations.
The gold in this conglomerate reef is partly of detrital origin and partly of the genetic character of ordinary vein-gold.
Beds between beds of sandstone and shale, and S becomes increasingly detrital in character as it is traced northwards.
The old land area still existed to the north, but doubtless much reduced in height; against this land, detrital deposits still continued to be formed, as in Scotland; while over central Ireland and central and northern England the clearer waters of the sea furnished a suitable home for countless corals, brachiopods and foraminifera and great beds of sea lilies; sponges flourished in many parts of the sea, and their remains contributed largely to the formation of the beds of chert.