Gitennes defines Rio Suro with underground drilling

Junior Gitennes Exploration (GIT-T) has launched an underground drilling program on the Rio Suro zone at its Virgen property in northern Peru in an attempt to outline a proven reserve to a vertical depth of 150 metres.

The bulk-tonnage gold prospect comprises 2,600 ha in an area of high rolling hills about 180 km east of Trujillo. Elevations span from 3,400 to 4,100 metres.

The deposit forms part of a high-sulphidation epithermal system, hosted by Cretaceous sediments and Tertiary andesites, and Gitennes has determined that the gold occurs in linear, north-trending zones of fracturing and breccia, sandwiched between major faults and in association with either oxide or sulphide minerals.

The Rio Suro zone is an oxide body amenable to heap-leaching. Extending beyond the oxide mineralization to the north and east is a separate zone of sulphide mineralization called Rio Suro Norte. The combined zones extend over 1,200 metres along strike, with widths of up to 220 metres in the south, pinching to 45 metres in the north.

As of April, Gitennes had completed 63 diamond drill holes and 22 reverse-circulation holes totalling 9,700 metres. However, 35 of these holes either experienced poor recoveries or did not reach their intended depth. In addition, 328 metres of underground tunneling and development were carried out in the southern portion of the Rio Suro zone.

Work to date indicates that Rio Suro contains at least two high-grade zones; one along the eastern edge, and the other at the southern end. While neither zone has been drilled in detail, the eastern zone has a minimum length of 120 metres, a true width of 8-40 metres and a vertical depth of 65 metres.

The eastern zone is offset by faults at several locations but remains open along strike and to depth.

A crosscut, driven in an east-westerly direction across the northerly striking portion of the higher-grade breccia, averaged 10.56 grams gold per tonne over 44.8 metres. The crosscut was completed at the northern end of a 66-metre-long drift that was driven along strike of the eastern edge of the breccia body. The drift encountered 19.5 metres of fractured and brecciated quartz arenite averaging 0.47 gram, before hitting the eastern edge of the breccia zone, which averaged 4.53 grams over a strike length of 46.7 metres.

Other sections of the Rio Suro zone consist of lower-grade mineralization ranging from 0.3 to 2.5 grams. Moving to the west, the grade gradually diminishes. The western limits of the zone will be defined by mining costs.

As part of the current underground drilling program, a fan of five holes was drilled perpendicular to the zone from an underground station in the northern crosscut. The holes were drilled from the edge of high-grade oxide breccia into lower-grade mineralization. Results are as follows: * Hole 4 was drilled to the west, up towards surface at an angle of plus 45. The hole returned 30.3 metres averaging 6.02 grams.

* Hole 1 undercut hole 4, intersecting 25.2 metres of higher-grade breccia averaging 4.03 grams before passing into 42.9 metres of lower-grade fracture breccia averaging 0.92 gram. Hole 1 was collared at an angle of minus 15.

* Steepening to minus 40, hole 2 intersected 13.5 metres of higher-grade breccia averaging 4.76 grams before encountering a lower-grade 53.99 metres averaging 0.6 gram.

* Hole 3 was lost and re-drilled as hole 5 at an angle of minus 80. The fifth hole passed through 12 metres of higher-grade breccia averaging 9.84 grams before cutting 157 metres averaging 0.78 gram.

* Hole 6 was also drilled at minus 80, but to the east, hitting 36.27 metres averaging 8.72 grams before intersecting 132.59 metres of lower-grade fracture breccia averaging 0.95 gram. Underground drilling is continuing from a second station, 60 metres to the south.

Gitennes says underground results are proving better than expected; the high-grade portion has increased 30% in volume, with overall gold grades increasing slightly. Grades in the lower-grade western portion are said to average twice the grade predicted by initial surface holes. Silver values are also higher.

Metallurgical testwork on the underground samples is confirming initial results. Gold recoveries range from 79% in sub-cutoff grade mineralization to more than 95% in high-grade material. A full-scale 60-day column leach test is in progress. Recoveries are exceeding 63% after only the first 15 days. Gitennes expects gold recoveries on run-of-mine material will run in excess of 80% and higher on crushed rock. A scoping study will follow.