Ambrex reassesses Aripuana

Resampling an old drill hole has led to the discovery of high-grade gold mineralization in oxides at the Aripuana polymetallic property in northwestern Brazil.

Operator Ambrex Mining (AMBX-C) reports that the first 23.1 metres of hole 9, drilled in 1996, averaged 18.11 grams gold per tonne. The hole, which was drilled at minus 60 to the northeast, was resampled as part of an on-site review of unexplained soil anomalies. (Geochemical anomalies stretching 300 metres along a southeastern direction coincide with the intercept and extend 90 metres down-slope from the ridge on which it rests.)

Two other holes drilled in 1996 on the same section as hole 9 intersected primary copper-gold mineralization at vertical depths of 80 and 145 metres. As well, garimpeiros (local miners) reportedly extracted 2,250 oz. gold from a 6-metre-wide, northwesterly striking shear zone 600 metres to the southeast, and follow-up trenching by Ambrex in the footwall of the pit has returned up to 11.87 grams over 6 metres.

Ambrex now believes the two gold-bearing areas might represent a late-stage overprint of the mineralizing event that gave rise to the nearby Valley and West stratiform deposits, or additional bodies of a similar geological nature. Combined, the deposits host drill-inferred and -indicated resources of 11.6 million tonnes grading 6.29% zinc, 2.25% lead and 0.07% copper, plus 64.7 grams silver and 0.25 grams gold per tonne. The resources were calculated by A.C.A. Howe International, using a cutoff grade of 3% zinc and following the Australian classification scheme.

Ambrex holds a 53.3% interest in Aripuana through its Brazilian subsidiary Minerais Rio Taboco. The remaining interest is divided between Ourominas Minerals (OMI-T), with 30%, and St. Genevive Resources (SGVE-C), with 16.7%.