Two significant niobium deposits have been defined to date and are named Boa Vista and Morro de Padre deposits. These deposits are hosts by igneous rocks which occur as swarms of thin dikes, forming a stockwork of crosscutting dikes in the upper zone and varying to individual mineralised thicker dikes at depth.

Niobium mineralisation is associated with nelsonite vein which vary in thickness and orientation forming stock work style deposits. Containing magnetite-apatite-carbonate composition economic mineralisation is exclusively associated with the mineral pyrochlore. The nelsonite veins are hosted within a variety of pre-existing lithologies including amphibolite and fenite, a metasomatically altered rock believed to originally comprise phyllite. Phlogopite alteration may also be associated with the carbonatite veins, where it commonly occurs as haloes surrounding the veins and overprinting the fenite. To a lesser extent phlogopite occurs as selvages to the nelsonite veins.

Both the Boa Vista and Morro de Padre deposits occur as pipe-like bodies consisting of sub vertical major feeder structures that permit vertical passage of the deep-seated carbonatite magmas to shallower depths where the dykes split into a complex stockwork of veins and veinlets. The stockwork zones are approximately 270m (N-S) by 350m (E-W) and are considered to be a result of magma degassing in response to reducing confining pressures and the formation of multiple sets of tensional ........

The niobium ore from the Boa Vista mine is mined using conventional open-pit mining methods in multiple benches in a confined mine. Operations commence with waste stripping, or the removal of the organic waste soil layer, which covers the economically viable ore to be explored. It is carried out by backhoe loaders, which remove the material and load the waste onto the trucks, which transport and unload the material in the waste dump.

The Boa Vista pit has been mined since 2000 with fresh material reached in 2014. Overall slopes in the oxidized ore are 25 to 30o and bench face angle (BFA) of 65 degrees with 5-m high benches. Fresh rock have overall slopes of 50 to 53o, BFA of 85o and 10-m high benches.

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