These coins were produced at the Royal Mint (UK). The designs were modelled by Gordon Summers and Robert Elderton.
Gordon Summers is now Chief Engraver at the Royal Mint. This is his recollection of his role in the modelling of these coin designs.
The whole series came in as a general design from Tanzania but had to be reworked in small ways in order to make the concept coinable. Although I undertook this process for all of the coins, I could not claim to be the designer.
The obverse was an existing design which we needed to resize, digitally, for the larger coins.
I recall producing the models for the Giraffe, Impala, Gazelle, Zebra, Crocodile and the 10,000 Shilingi and would assume that Bob (Robert Elderton) worked on the others.
Interestingly, these were early days for our digital technology and we had a tendency to do considerable hand-work on the master tools. In this case I had the job of hand-punching the animal names on to all of the Matrices (Incuse versions of the master tools) as they had not been included in the original models. Additionally I had to hand engrave the couping on the neck of the gazelle, as it was interfering with the denomination. As the youngster in the department I got all of the fun jobs!