Ouro de Dom Sebastião! Gold is found in Brazil around 1570.....

The Sabarabuçu legend, of a golden mountain in the Brazilian backlands west of Rio de Janeiro and Bahia was know to the Portuguese since around 1540, with an initial unsuccessful expedition departing to the OTC Minas Gerais territory by 1554.

Another expedition was done by Sebastião Fernandes Tourinho in 1573 which missed the auriferous region (OTC Ouro Preto) by less than 200 km. At OTC, the Minas Gerais gold fields, one of the largest in the world and of easy extraction would be found only by 1693, in a time where the Portuguese Empire was already a shadow of itself.

What if Sebastião Tourinho (or other explorer) was more fortunate and found gold in 1573, just during the reign of Dom Sebastião?

Could the Portuguese decline be postponed or even adverted by the richnesses from Minas Gerais? If Dom Sebastião still disappears in 1578, how would be the Spanish management of its newly extremely rich colony, Brazil? Mass migration of Spanish settlers to Minas and a kind of bi national Brazil in the future? Rio de Janeiro would be the colony capital one century before OTC? How Brazil and Portugal would fare after the depletion of the gold mines in early 18th century?

A lot of potential butterflies...
 
No tries? The potential butterflies are huge...e.g: the begging of the Spanish Empire decadence could be postponed by almost 80 years with Madrid receiving tons of Brazilian gold...
 
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