Balabag Gold-Silver Project

The Balabag Gold-Silver Project is located within the northeastern part of the known gold district of Zamboanga Peninsula occupying the municipality of Bayog, Zamboanga del Sur and the municipalities of Diplahan and Kabasalan, Zamboanga Sibugay. The Project is within a granted mineral agreement denominated as MPSA-086-97-IX with a total area of 4,779 hectares. The Balabag MPSA is approximately centered at coordinates 122˚55’30” East Longitude and 7˚53’30” North Latitude.

The nearest municipality to the mining property is Bayog, which is accessible from either Pagadian or Zamboanga City through the Zamboanga-Pagadian National Highway, then through an 18-km gravel dirt road from the highway junction at Imelda or Buug, Zamboanga del Sur.

Four main lithologies were identified within the Balabag mining area which include the sedimentary rocks, volcanic rocks, diorite, and andesite-dacite porphyry. The sedimentary rocks correlate with the Paleocene and Early Miocene Sirawai and Anungan Formation, respectively. The volcanic rocks, on the other hand, correlate to the Late Miocene Soleplep Volcanic Complex and the diorite to Late Miocene Vitali Diorite. The youngest rock unit interpreted in the area is the andesite-dacite porphyry which can be correlated to the Pliocene-Pleistocene Sta. Maria Volcanic Complex.

The Balabag deposit is a Low Sulphidation Epithermal (LSE) vein system hosted in andesitic lava flows and pyroclastics. The three major quartz vein systems identified at the Balabag Hill are the Tinago-Unao-Unao veins to the north, Miswi veins in the east and Lalab veins to the south.

Various epithermal quartz vein characteristics were identified such as colloform, crustiform, massive, drusy, vuggy, comb and cockade textures. Multiphase brecciation textures are dominant mainly due to several pulses of rising hydrothermal fluids. Quartz stringers and quartz stockworks also occur adjacent to most quartz veins ranging from hairline to centimeter sizes.

The geometry of the veins and the associated stockworks are generally sub-horizontal at the Tinago and Miswi areas while a sub-vertical attitude of veins is exhibited in the Lalab area. The quartz veins and breccias are bounded by typical alteration zones in an epithermal environment such as silicification, argilization and propylitization.

Multiple exploration programs were carried out by TVIRD in Balabag. In 2006-2007, detailed drainage geological mapping and sampling were conducted around Balabag Hill with a total traverse length of 13.5 kilometers. This was followed by a more detailed geological mapping of roadcuts, creeks and major streams. Test pitting was initiated after several surface samples returned anomalous gold values.

Trenching along the projected strike of the Tinago, Lalab and Miswi veins was also implemented to determine vein continuity. The trenches were spaced about 50 meters apart and oriented almost perpendicular (northwest to southeast) to the general trend of the veins.

TVIRD conducted mapping and sampling of some of the artisanal miners’ underground tunnels after small-scale mining activities were stopped in Tinago, Unao-Unao, Lalab and Miswi. This was done to precisely measure the attitudes of the veins, verify their width and strike continuity as well as collect vein samples.  Sample points selected underground were recorded with reference to the distance from the tunnel’s portal.

TVIRD started its own drilling program on November 17, 2005 with the first hole collared at central Tinago area. Two drillholes were completed during the year incurring a total of 131.30 meters. The following year, drilling accelerated and 57 drillholes at 50-meter drill spacing were completed with a total meterage of 6,822.10. Further to the encouraging results, TVIRD embarked on an infill drilling campaign in 2007 with drillhole spacing reduced to 25 meters. Accumulated drilling meterage incurred through this initiative in 2007 was 4,021.30 meters from 42 drillholes.

In February 2010, TVIRD resumed infill drilling in Unao-Unao area after a three-year hiatus. Several subsequent phases of drilling were completed until the second quarter of 2012, including sterilization holes along the proposed sites of the mill, mine camp, waste dump and tailings storage area. A total of 177 drillholes incurring a total of 21,960.35 meters were generated from year 2010 to 2012.

More holes were drilled to the west of Balabag Hill to chase the possible western extension of the Tinago vein system.  Drilling resumed in February 2013 and another 18 holes with a total of 1,220.55 meters were completed until April 2013.

Another series of infill drilling under Phase 1 to 5 exploration program was initiated during the latter part 2018 and continued through to last quarter of 2021, incurring an additional 139 drillholes with a total of 13,663.15 meters.

Phase 6 drilling took place in year 2022 with 55 additional holes and cumulative meterage of 4,850.35, developing resource potential towards West Tinago.

Reverse Circulation (RC) drilling campaign was also implemented from March 2023 to September 2023. A total of 118 holes with a cumulative meterage of 7,632.9 was completed within Balabag Hill, majority of which were drilled at Miswi extending to upper Lalab area to refine the prior geological interpretation. North Tinago, Unao-Unao and Yoyon were also drilled to test the down dip extent of the mineralization. 

TVIRD continued its exploration efforts by reverting to diamond drilling under the Phase 7 and 8 campaign in 2024. A total of 91 holes with a cumulative meterage of 10,013 was drilled from February to July 2024 in order to delineate additional resource at Miswi, Main Tinago and Lalab areas. Almost 50% of the total meterage were focused on defining the down dip extension of the Miswi orebody. Two deep holes, around 500 meters each, were drilled to test the sub-vertical veins in Lalab.

As of February 2022, the updated Measured and Indicated Mineral Resource for the Balabag Gold-Silver Project at a cut-off grade of 0.4 g/t AuEq is 4.97 million tons at 1.76 g/t Au and 34.54 g/t Ag for 2.21 g/t AuEq. The estimated Inferred Resource is 472,120 tons at 1.44 g/t Au and 17.23 g/t Ag for 1.67 g/t. The projected Mineral Resource incorporates drilling data from 2005 up to end of Phase 5 drilling campaign in 2021.

The refined geological model and updated mineral resource estimate were verified and certified by an Accredited Competent Person (ACP) under the Philippine Mineral Reporting Code (PMRC) 2020 Edition.

Table 1: Mineral Resource Estimate of the Balabag Gold-Silver Project, February 1, 2022 (L. A. Sosa)