In actual fact Doyle's Lost World was located in the plateau region of Guyana. This region abounds in rich veins of gold and silver. Diamonds are dredged from the rivers and the northern half of South America yields emeralds and a number of other precious and semi - precious stones. Further to the west, the Spanish extracted murcury ( Hg )and silver from ajoining mountains to fuel the economy of King Phillip and enrich English privateers.Most of the indians and criminals engaged in extracting the Hg died horrible deaths. Bauxite is common, but I'm not aware of any native copper or tin for the construction of cartridges.
Faustus