What do you know about the Caciques de Venezuela gold series of the 1950s?

Gold "tokens", apparently minted by/for the Inter Change bank of Switzerland featuring infamous Venezuelan indigenous chiefs. How many were made? For what purpose (other than gold?)? Mintages?
I've come across a few in the wild. But I'm thinking of trying for a full set of the larger versions (they came in different sizes). Information seems to be spotty.
But I love how outrageous and mid-century the designs are!
We are like children who look at print and see a serpent in the last letter but one, and a sword in the last.
--Severian the Lame
--Severian the Lame
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