A rather large example of this iron, titanium oxide from Erongo. This is one of the minerals known to occur somewhat more rarely on the mountain, and I suspect one that also gets overlooked by international dealers as it isn't exactly a colorful fluorite on aquamarine. To put it in perspective, there are only 6 pictures of this material on mindat.
According to the Mineralogical Record's "Erongo" issue, the orange surface coating is mildly radioactive.