Hi Rhiannon
The glimpse we got of San rock art was all too brief. We only went to this one site (one of the best) at Twyfelfontein, though there are petroglyphs and paintings all over southern Africa. Some good ones in the Drakensburg mountains I believe...

The carvings are dated using stuff found near them - so not an exact science at all. I see no reason why a site like the one we saw wouldn't have been added to over centuries/possibly millenia. The theories we were told about what they were for were very very dodgy. Our guide was most quoting stuff she had said a zillion time before, so it was hard to ask stuff and get a considered answer.

I wish I had the answers to your Qs, Rhiannon, but I really haven't a clue about the rocks or the techniques used to peck them! But you should bear in mind that the climate is, and almost certainly was, VERY different to here. And we're mostly talking baking heat.

I reckon that the illusion of sponteneity and simplicity can be worked into something that takes a long time to execute. You could paint the design in using ochres first, of course, and get your apprentice to do the pecking out work, for example.

We'd like to have seen the White Lady of Brandberg (a very famous rock painting which I believe has been very badly misinterpreted) - and we did drive incredibly close to it - but we were on a fixed itinerary and had an appointment with 100,000 cape fur seals...