Discovered in 1917 in the Maxixe mine at Minas Gerais, and subsequently in other places in Brazil. It is a rare variety of beryl of a beautiful intense blue colour which unfortunately fades with time, as it is unstable. Unlike the aquamarine where the blue colour is due to the presence of iron, the maxixe owes its colour to the presence of nitrate ions. Our specimens were subjected to analysis under a mass spectrometer thanks to which we could confirm that they were maxixe.