After extracting practically all the gold and diamonds from the captaincy of Minas Gerais, Brazilian and foreign politicians and naturalists were looking for new sources of wealth in the form of ores. However, the news of the discovery of copper and cobalt mineral deposits, made by José Vieira Couto (a naturalist from the city of Diamantina), were discredited because the locations indicated or even the analysis performed may have been done incorrectly or even intentionally altered by the naturalist in order to draw the attention of the Portuguese Crown or seeking ways of obtaining social and political promotion among the colony’s governors.

Saltpeter demanded for a long-time strategic attention in view of its importance in the form of gunpowder by the governments of many nations. The sources of this mineral in Brazil were almost always associated to the soil in caves, which was extracted because of a limited amount of that precious salt. The first references pointed out that saltpeter was first discovered in the São Francisco basin in regions of the south of the Captaincy of Bahia and in the north of Minas Gerais. Some historical documents show that the Serra do Baldim was the object of intensive mining activities of saltpeter from its caves and the product became the focus of conflicts and left scars on the walls of some limestone caverns.

In the year 2019 the periodic table of the elements will celebrate 150 years. A frequent misunderstanding says that palladium might have been initially discovered in samples from Brazil. Indeed it was found in the country in the early nineteenth century, but this discovery was preceded by other findings elsewhere in South America. This article will report its discovery, both abroad and in Brazil, as well as many other related aspects.

At the turn of the nineteenth century, a frantic search took place in Minas Gerais for minerals that could prove to be of economic value and thus compensate for the decline in the production of gold and diamonds, the mainstay of the economy in the preceding century. This article addresses the search for new mineral wealth, involving the work of many different explorers and their multidisciplinary research, and particularly the unsuccessful efforts directed to finding and obtaining lead and silver in sizable amounts as two such possible replacements.