Tiberon advances Nui Phao

Vancouver — With a newly completed scoping study in hand, Tiberon Minerals (TBR-V) is gearing up for a round of metallurgical test work on the Nui Phao polymetallic project in Vietnam.

The bench-scale metallurgical study is slated to start next month. It is the next step in advancing the potential open-pittable tungsten resource.

Drill results to date indicate that mineralization:

• extends for 2 km in an east-west direction;
• extends for 300-400 metes in a north-south direction; and
• is a flat-lying body up to 160 metres thick.

Four rigs are turning on the property.

Mineralization is hosted in skarns and their greisenized or retrograde equivalents. Greisenization refers to a replacement process whereby quartz, fluorine and micas — as well as accessory minerals like tourmaline, rutile, cassiterite and wolframite — replace skarns or granites.

At Nui Phao, the greisenization consists of high fluorine, beryllium, tungsten, tin and limited rare earth metals, which have replaced granitic dykes and earlier-formed skarn units.

A scoping study was completed by New Brunswick-based Thibault & Associates. It determined that tungsten, the primary commodity, is easily recoverable by both gravity and flotation methods.

The processing concept envisions the use of gravity preconcentration to raise the grade of tungsten trioxide from 0.5% to 1%. A gravity concentration test increased the tungsten grade by 3.8 times and recovered 94% of the tungsten (concentrate and middling) using a minus-150-micron grind.

Preconcentration would be followed by the recovery of tungsten, copper and fluorite through a combination of gravity and flotation. Bismuth may be recovered by hydrometallurgy. As a final step, the tungsten concentrate would be processed into a high-purity ammonium paratungstate.

The potential recovery of the gold content was not included in the study. It will be addressed as part of an upcoming bench-scale study.

This new study will evaluate the relationship of grade recovery to grind size and other dependent variables. It will also assess how the operations will comply with grade and market specifications and environmental guidelines. It will include a design of the process flow-sheets, equipment sizing and layouts.

The Nui Phao project lies in the Dai Tu district of Thai Nguyen province, about 80 km northwest of Hanoi.