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Jan 23, 2003
Downgrades Valderama Zone but Indicates Porphyry Copper-Gold Prospect on Asparin Hill Target

Tony Climie, P. Geol., President of Mindoro Resources Ltd. ("Mindoro") is pleased to advise results of a Phase 2 reconnaissance drill program on the Pan de Azucar Project "PDA"), Philippines, carried out in late 2002. Release of results has been delayed while awaiting check assay results and an important petrographic report that have produced encouraging results on the project potential.


A 2001 scout drill program (1,041meters (m)) within the PDA volcanic caldera, discovered the Valderama massive, pyritic sulphide zone, with promising copper, gold, silver and zinc values, e.g. drill hole PDA-03 with 37.1 m of 0.8% copper, 1.87 g/t gold, PDA-06 with 37.00 m of 0.14 % copper, 1.25 g/t gold , and PDA-08 with 40.25 m of 0.69 % copper, 1.21 g/t gold, 4.34 g/t silver, and 0.63% zinc.

The objective of the second drill program was to further delineate the mineralization. Five holes were drilled, or deepened, for a total of 431.25 m. The Phase 1 drill program had suggested that a copper-gold-silver-zinc zone of potential economic interest was present. A full technical report was filed on SEDAR on January 21, 2003 (

Location of the drill holes completed is shown on Figure 4, together with interpreted outline of the zone. Figure 9 is a long section through the zone. The Phase 2 results for the Valderama Zone were of lower tenor than those for Phase 1. Best results were: PDA-12 with 32.26 m (46.82- 79.08 m) at 0.59 g/t gold and 36.24% sulphur; PDA-13 with 6.00 m (6.85 - 12.85 m) at 0.59% copper; and a 9.00 m (12.85 - 21.85 m) section with 0.41 % copper and 0.49 g/t gold; PDA-14 with 7.80 m (70.70 - 78.50 m) at 0.29 g/t gold and 42.08% sulphur; PDA-15 (a re-drill of PDA-13 which was lost due to faulting) with 3 m (10.00 13.00 m) at 0.16% copper and 0.66 g/t gold, as well as 8 m (16.00 24.00 m) at 0.33% copper, and 9 m (24.00 33.00 m) at 0.54 g/t gold and 34.66% sulphur.

The Phase 2 results indicate that the later copper-gold-silver-zinc mineralizing event (superimposed on the massive pyritic sulphide zone) was irregular and erratic. Although the Valderama Zone is still under-drilled, and open in several directions, the Phase 2 results have reduced the potential for an economic copper, gold, silver, zinc resource. The zone is open to the north, for a further 250-300 m, to the property boundary, where gossanous outcrops are present.

Based on drilling to date, the Valderama Zone averages between 36% and 40% sulphur, is near-surface, and a few hundred meters from tide water. It may, therefore, have potential for a low-cost sulphur source for sulphuric acid production for treatment of the numerous lateritic nickel deposits, expected to go into production in the Philippines and elsewhere in the region, and for fertilizer production. Mindoro's main priority, however, will be other copper-gold targets on the PDA Project and Mindoro projects elsewhere. The Valderama epithermal replacement zone has, since 1997, been considered by Mindoro to be the high-level reflection of an adjacent porphyry-copper-gold system.

A shallow (45 m) drill hole (PDA-16) was completed on the Asparin Hill target, approximately 700 m west of the Valderama Zone, to test an area of gossanous quartz-alunite boulders, the strongest geochemical anomalies seen on the project, a coincident circular topographic depression (300 m in diameter), and a broad magnetic anomaly (see Figure 4).

PDA-16 intersected intensely altered dacitic rocks. Petrographic work on core was carried out by E. Comsti, M.Sc., who has a high degree of familiarity with Philippine copper-gold systems (see Jan. 1/03 Technical Report, Appendix 3 - Petrology Report on SEDAR). Comsti recognised three alteration assemblages; (a) an earlier pervasive illitic/sericitic alteration, which is overprinted by (b), K-silicate alteration, characterized by hydrothermal biotite and minor chlorite, and itself overprinted by (c) later sericite-chlorite alteration. Disseminated and veinlet chalcopyrite mineralization occurs in PDA-16, and associated with the potassic alteration; both are characteristics of porphyry copper systems.

Comsti concludes:
  • "The occurrence of chalcopyrite together with K-silicate (potassic) alteration indicates a possible porphyry copper mineralization at depth."
  • "Asparin Hill is a highly prospective site for the search of a high level intrusive or breccia body, which may host porphyry style mineralization"
  • "The presence of hydrothermal biotite in two of the drill core samples from Asparin also strongly supports this claim."
  • "Intense silicification in the area has rendered the host rock highly resistant to erosion resulting in topographic prominences. This intense alteration may be related to the formation of a diatreme or a hydrothermal breccia pipe below".

Figure 11 is the exploration model of PDA, showing the interpreted relationship between the Valderama Zone and a porphyry system below, and adjacent to Asparin Hill. PDA occurs in a known porphyry copper belt; four deposits were previously mined on neighboring Negros Island.

Future work at PDA will focus on the Asparin Hill porphyry copper-gold target. However, a major partner will be sought for this work, while Mindoro focuses on other promising targets in the Philippines. A major company has expressed interest and has just completed a site visit to PDA.

Mindoro is a Tier One Company listed on the TSX Venture Exchange (symbol MIO). The Company is exploring for gold and gold-copper in the high-potential magmatic arcs of the Asia-Pacific Region and is presently focussed on six promising projects in the Philippines.

For further information, contact Penny Gould, Executive Vice

Phone: (1-780) 413-8187

Fax: (1-780) 426-2716



The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release.

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