Terminalia prunioides
These attractive seedpods belong to the Purple-pod, or Lowveld, Cluster-leaf, a densely branched shrub or small tree that is found in our Limpopo and Mpumalanga provinces. It proliferates in clay-like soils, often in rocky areas next to large rivers, and is heavily used by browsing animals.
Purple-pod Cluster-leaf
Purple-pod Cluster-leaf
Purple-pod Cluster-leaf
DeWetsWild 
I have really enjoyed seeing this lovely tree when on trips in Botswana. Your photos evoke happy memories.
I don’t think I have seen this tree before, so thank you for this excellent photographic introduction!