Khoikhoi name of Rooiberg, some 10km from Eksteenfontein . Translated from Afrikaans means 'red mountain'.
References
South African Place Names by Peter E. Raper
Further Reading
https://sahris.sahra.org.za/sites/default/files/additionaldocs/Richtersveld%20Draft%20EIR%20Chpt%206.pdf
https://wikivisually.com/wiki/Eksteenfontein