Stamp on Hill Gold Mine – Bolivia 1987.
Exfivia 87 Philatelic Exhibition was held in Potosi in Bolivia. Potosi is one of the highest cities in the World at 4,090 metres. But it most famous for its Silver ore Mine hill called Hill Gold Mine. Spain established a Colonial Mint here and it took Silver to Spain via the Ilama and Mule trains and Spanish treasure fleets.
Bolivia issued a stamp on Exfivia featuring the Hill Gold Mine on 05 Aug 1987.