This is a dangerous forgery that could easily fool one at first glance. Wide roulette stamps of the 1st ZAR and 1st British Occupation are rare, and collectors may not have well-formed mental images to recognise them.
It was made from a genuine imperforate stamp by cutting small half holes into the edges. The forger missed the fact that the technique created perforation holes rather than roulette stubs as explained below. That is, the roulette impression is the wrong way around. Rouletting creates thin straight cuts into the sheet between stamps, leaving little stubs that can easily be broken by tearing along the line as shown below.
Once the stamps are separated the stamp edges exhibit short stubs with straight edges as shown below.
This contrasts with the half holes of the forged stamp shown below.
Another clue that there is something suspicious about this stamp is that the wide rouletting used on ZAR stamps did not always work as well as intended and often examples are roughly torn.
It will be interesting to hear whether other collectors came across similar items and suggestions of how the holes could have been done. Please contact Danna with any information.