On a blog called Numismática Bentes, I found a fairly long written history (in PT) of moedas coloniais (colonial coins) of Brazil as well as some pictures of these coins that I hope he/she doesn’t mind me posting. For a quick conversion, one modern-day real, with inflation considered, is worth 2,750,000,000,000,000,000 réis.
(from Minas Gerais, worth 20,000 mil réis, in 1720s)
(from Minas Gerais, worth 12,800 mil réis, in 1720s)
(from Minas Gerais, worth 960 réis, in 1808-09)
(worth 480 réis, from late 1600s to early 1700s)
(Dutch-made, from Pernambuco, worth XII florins, in 1645)