Hi Lew,
thank you for your comments

,
The knobkerries were bought individually, at different times. The smaller one was described as a Zulu 'shield beater'
The larger, hand tooled one seems to be made in the Zulu 'mould' (mold

) I have seen provenanced Zulu knobkerries that are not made from the usual bi-coloured wood and number of which were hand carved. In fact, I have been told that the majority of the bi-coloured type are early 20th C onwards (an opinion of a 'Zulu' collector)
Unfortunately, Spring hardly mentions knobkerries in "African arms and Armour" and Stone's " A glossary.......Arms and Armour...." mentions even less.
Tried to search google for "Gogo club" in image search..but just get pictures of scantily clad females

not a bad thing, but not really helpful
All the best
David