NEWS RELEASE
DRILLING CONFIRMS COPPER-GOLD ZONE IN SANTA ISABEL PORPHYRY
During the last quarter of 1996, SAMEX completed 1,510 meters of core drilling and 24.2-line kilometers of induced polarization (IP) survey as part
of continuing exploration on the Santa Isabel Porphyry Project in Southwestern Bolivia. The drilling results confirm the presence of potassic alteration
hosting copper-gold-mineralization at depth within the central part of the Vera Cruz Zone. A strong IP chargeability response indicates that a similar
target, at much shallower depth, underlies an extensive area in the eastern part of the porphyry complex ("Mercedes Zone") which is uplifted along the
east side of the Mercedes Fault. An eight-hole drill program will begin this week to continue testing these zones.
The recent drilling consisted of four holes (#9, 10,11,12) located in what is now known to be a down-dropped structural block on the west side of
the Mercedes Fault. Drill Hole #10 was collared in and intersected the zinc-rich part of the potassic core, but was halted at a depth of 350 meters.
The deepening of this hole is being considered. Hole #11, drilled south of the Linares Zone, was stopped in propylitic-altered rock at a depth of 210
meters, short of the intended deep IP target. Hole#12 penetrated a thick (+/- 200 meter) interval of younger volcanic rocks and entered a strongly
clay-chlorite-altered breccia which was cored to the final 450-meter depth.
Hole#9 intersected and bottomed in copper mineralization after being drilled to a depth of 500 meters within the east-central part of the Vera Cruz
zone. Mineralized, potassic-altered, porphyry intrusion was penetrated over the lower 350 meters of the hole. Disseminated sphalerite was
encountered throughout the interval from +/- 170.0 to 455.0 meters which averaged 0.25% zinc plus anomalous, silver, gold, and arsenic. From 455
to 500 meters, the hole intersected copper mineralization consisting of disseminated and veinlet chalcopyrite which is locally partially replaced by
chalcocite. Assay results for this 45 meter interval averaged 0.035% copper and 0.16% zinc, however, sludge analyses suggest that this interval likely
contains closer to 0.17% to 0.24% copper as well as 0.312 to 0.417 g/t gold. The higher copper values in the sludge produced from the core cutting
indicates that much of the chalcopyrite and chalcocite was washed out of the rock as evidenced by the presence of vugs with remnant copper sulfides.
The analytical results over the entire hole show sulfide-metal zonation changing with depth, from zinc-to more copper and gold, which suggest that this
intercept represents the top or transition into the copper zone of the porphyry system. Penetration deeper into the copper mineralization will be
pursued by drilling in the altered porphyry of the uplifted Mercedes Zone, where geophysical results indicate that a large zone of potassic-altered
porphyry may be present at a shallow depth over a 1,500 by 800 meter area.
In addition to the above targets, results of the IP survey and past drilling have identified what is possible a large breccia pipe concealed beneath thin
glacial cover in the center of the porphyry complex. The breccia pipe is steeply plunging with a long dimension of 1100 meters and an average width
of 700 meters. Re-examination of core drilled in two holes (DDH-SI-96-4 and 5) at the extreme west margin of the body suggest that rocks once
considered to be boulder/cobble in -fill, is likely a hydrothermal breccia with altered rock-flour matrix and rounded to subangular clasts of mineralized
sericite-pyrite porphyry. Although variably leached, geochemical results show that the rock contains considerably elevated values of copper and
molybdenum compared to surrounding sericite-pyrite-altered porphyry. The potential of the breccia pipe will be further evaluated by a separate core
drilling program scheduled to start during the first quarter of 1997.
ON BEHALF OF THE BOARD OF DIRECTORS,
"Jeffrey P. Dahl"
Jeffrey P. Dahl - Vice Chairman |
