In the mid-eighteenth century, the gold exploitation in the mountains of Minas Gerais reached its maximum. The Portuguese Crown demanded the collection of “quinto dos infernos” (tax on extracted gold), which was not always paid by "just men". In 1763, the Crown creates the “Derrama” (a decree) in order to receive the payment of taxes owed to Portugal. It increases the tension in the area and a movement for independence starts to be organized. Frustratingly, their leaders are killed or banished. The head of the Ensign Joaquim José da Silva Xavier, Tiradentes, is exposed in Vila Rica’s central square to demonstrate the futility of the struggle for freedom.
Vila Rica, nowadays the city of Ouro Preto, was the scenario for all a struggle for independence and also for the economic development of Brazil. The Inconfidentes were sure that the submission to the Crown was the factor impeding the country's economic development.
250 years after the decree of the first Derrama, the biannual event of the Brazilian Society for Metrology, Metrology 2013, will be held in Ouro Preto under the theme:
Metrology and Quality for Sustainable Development