Natural dark brown and black coloured fine banded agates are found on the dumps of the Soutpan Diamond Mine near Wolmeransstad. At this place mining operations upto a depth of 30 feet below surface are done exploiting diamond bearing gravel. The origin of this gravel as well as the origin of the agates is still unknown.

The agates are occuring as complete edge-smoothened nodules up to a size from 6 inches. Besides the remarkable colour (so called natural “Onyx”) the formation of chalcedony/ macro-quartz interlayers and “ water-level-agates” is very interesting.

More informations about this material and other southafrican gemstones are offered at the homepage of afrigemtec