Then there is the detrital diamonds of the west coast

Those diamonds are not found in kimberlite pipes but in the sediments brought to the west coast by the Orange River. To get there you have to drive through a very dry plain. As you arrive from the desertic inland the first sign that the coast is approaching is the bank of grey fog in the distance.
The town (Port Nolloth) is in fog most of the time, they say 8 months of the year, and is amazingly cool even though 10 kilometres west of it is probably one of the hottest spot of South Africa. It is always hard to take picture of the fog but just here are the diamond dredging boats in the harbor.

These are used to get diamonds on the bottom of the ocean along the coast. They basically vacuum the ocean bottom to catch all the gravel. Then the gravel is sorted out to find the diamonds. All diamonds found here, unlike those found in kimberlites, are gem qualities. The theory, and it makes sense to me, is that it is because all the diamonds which are not gem qualities are not as strong and are destroyed by the transport and weathering.

Over 80 kilometers of the coast are closed off and are behind fences. And by the way, they mean it. They really really do not want people wandering in those areas.
In this photo you can see the difference between the white clouds and the slightly grey fog coming off the ocean and hanging around the coast.