A low-sulphidation epithermal gold-silver system close to the world-class Escobal silver deposit.
Location and Access
The Holly-Banderas (HB) project is located in south east Guatemala, about a 3 hour drive from Guatemala City. Infrastructure is excellent and the project easily accessible by dirt road.
Ownership
100% Radius
History
The Holly and Banderas projects were discovered by Radius during a regional stream sediment sampling program in Eastern Guatemala conducted in 2001/2. The projects are close together and are now being considered as a single exploration project, the HB project. Originally explored between 2002-2004, Market conditions and a low gold price forced Radius to option the property to Glamis Gold Inc. in 2004-2005. The project was returned to Radius in 2005 and Radius re-activated HB in 2009 in response to the tremendous increase in spot gold and silver prices since 2003, and also in light of of the recent Escobal discovery made by Goldcorp 50km to the west of the HB project. Escobal contains over 318 million ounces of high grade silver and confirms that southern Guatemala is prospective for world-class precious metals deposits.
Radius' 90 square km area is highly prospective, with pervasive alteration throughout the region and multiple gold and silver anomalies in soil sampling, trenching and drill intercepts from historic work.
Radius diamond drilled 22 holes (±2,500m) at Banderas in 2002/3. Drilling confirmed the continuity of the mineralization both along strike and down dip in the majority of the zones tested. Glamis conducted two short drill programs mainly testing for bulk mineable gold in one zone at Banderas. Drill core from the various stages of drilling is stored by Radius in Chiquimula.
The Holly project adjoins Banderas to the northwest, at the intersection of two major geological structures, and was drill tested with a 2,000m (15 hole) program in 2003.
Major Deposits in Guatemala
Southern Guatemala hosts 2 major precious metals deposits: Escobal and Cerro Blanco. The region clearly has potential to host world class mineral deposits. The Escobal discovery was made after Radius finished its early exploration of the HB region and has driven management to re-evaluate HB.
The Escobal Discovery (Goldcorp)
The world-class Escobal Silver discovery, a grass roots discovery by Goldcorp, is about 50 Km due west of the HB properties and is hosted in the same Tertiary volcanic package. Silver grades and mineralization widths at Escobal are reminiscent of Mexico's major silver districts. The present resource is reported to be:
- Measured and indicated resources of 6.97 million tonnes grading 580 g/t silver and 0.63 g/t gold, (130 million ounces contained silver ounces)
- Inferred resources of 13.15 million tonnes at 443 g/t silver and 0.53 g/t gold (188 million ounces contained silver ounces)
Initial shallow drilling at Escobal produced low grade results, but deeper drilling (>250m) returned bonanza silver grades over impressive widths.
Intriguingly, the HB prospect is hosted by the same volcanic package within the same structural domain, and the initial shallow drilling conducted at HB between 2002-2004 returned some attractive results. However, the depth potential of the HB project remains untested.
Cerro Blanco (Goldcorp)
The Cerro Blanco gold deposit is located 35 km due south of Holly. It is a hot spring gold system where early shallow drilling again returned broad low grade results but later, deeper holes resulted in the definition of a gold resource of 1.94 million ounces (3.15 Mt at 15.5 g/t Au and 65 g/t Ag or 2.06 Moz Au-equivalent.)
Geology and Model of Banderas
The HB project is underlain by a sequence of andesites and dacites with volcanic textures including flows, vesicular flow tops and lithic tuffs, cross-cut and overlain by several flow banded rhyolite domes. Veins are typical low sulphidation epithermal quartz veins with colloform banding, chalcedonic bands, drusy centers, bladed textures (calcite replacement), and wall rock breccia clasts (often with earlier silica-pyrite alteration). Wallrock alteration consists of silica, buddingtonite, sericite, kaolinite, illite, and smectite, and is generally restricted to the immediate vein wall rocks. Argillic (clay) alteration is widespread and affects volcanic rocks over an area of at least 12 sq. km. underscoring the size of the potentially mineralized system.
Precious metal mineralization appears to be related to the rhyolite flow-domes, at least spatially, with some veins appearing to have a structural control and others appear contact related. Gold is hosted in the quartz/andularia banded veins with high grade gold and silver occurring in "ginguru" bands within the quartz. The hydrothermal system is exposed at a shallow (high) level, favourable for deeper exploration.
There are several veins trending about 320° - 340°; over strike lengths of over 2,000m (open) across a width of more than 700m. The main area tested to date by drilling is the eastern portion where the Pyramid Hill and M28 zones can be found. To date 6 holes have tested the Pyramid Hill structure below wide spaced trenches. All of the holes proved continuity of the gold/silver mineralization at depth and returned better gold results than the trenches they undercut. Some sections are below.
Just to the east of the Pyramid hill zone is the M28 zone (so named for the 28 gram Au discovery sample) which has been tested by 8 drill holes. Gold mineralization at M28, which occurs close to or on the contact zone at the base of the rhyolite flows, appears to be directly linked to the emplacement of the rhyolite (see below.)
Many other important target areas within the Banderas property remain untested such as the Zapote zone, a parallel structure approximately 1km to the west of Pyramid Hill zone, which has a strike length of over 3km and remains untested by drilling.
Geology and Model of Holly
The Holly project area is located 8km from Banderas. The project straddles the Jocatan fault, a regional east-west trending structure. Basement schists of the Santa Rosa group lie to the north of the structure while to the south, the same volcanic package can be found as previously discussed. A sequence of welded tuffs with a near vertical dip forms a prominent ridge at the contact with the schists. They tuffs are generally coarse lithic lapilli tuffs, varying to fine grained ash tuffs, with clasts of basement rocks (schists, metamorphic quartz) as well as volcanic rocks. The tuffs flatten to the south off the prominent ridge and at the base become concealed by a calcareous mudstone unit that is interbedded with a thin unit of very fine grained volcanic ash.
Tilting of the tuffs and mudstones was likely caused by movement along the Jocatan fault, which probably preceded the formation of quartz veining and gold mineralization (which cuts all lithologies, including the schistose rocks to the north of the ridge.) A rhyolite dome just to the south of the ridge may well be the driver for the gold /silver mineralization as at Banderas.
Narrow veins (0.2m-0.4m) with a 320 degrees to 340 degrees orientation occur predominantly at the ridge top and locally contain bonanza grades, for example the interval of 0.2 m @ 343 g/t Au and 10,374 Ag cut in HDD-005, and may represent leakage anomalies from an untested target at depth, potentially following the orientation of the Jocatan fault itself.
Radius drilled 15 holes for approximately 3,000m of drilling at Holly in the early 2000s. Some key holes, such as hole 005 which averaged 10.6m at 7.95 g/t Au and 264 g/t Ag, were never followed up and remain untested along strike and down dip although soil and rock geochemistry indicate continuity.
Work Plan
Follow up work at Holly-Banderas will include geophysics and significant drilling to test the down dip and strike extensions of the results previously obtained and also to investigate the many untested target areas.
