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Nov 19, 1998
Harimau Prospect - Phase 2 Program Preliminary Results
- Three extensive gold soil geochemical anomalies defined on Harimau prospect: Harimau Selatan, Harimau Barat, and Harimau Utara.

- Potential for near surface oxide gold resource identified at Harimau Selatan: Visible gold in soils.

- At Harimau Barat, soil geochemistry and geophysics indicate source of multiple stream sediment anomalies is related to intrusive / volcanic pyroclastic contact: Detailed follow-up in progress.


Tony Climie, P.Geol., President of Mindoro Resources Ltd. ("Mindoro"), announces preliminary results from the Phase 2 exploration program on the Tiris Project. Work has focused on detailed follow-up of the Harimau Prospect, a gold target identified by previously-announced strong and extensive stream sediment gold and silver anomalies (March 2, May 6, and July 27, 1998). The accompanying figure shows the location of the Harimau Prospect (West Block, Tiris COW).

87 kilometres (km) of grid lines were cut over the Harimau Prospect and soil samples collected every 25 metres (m) on 200 m-spaced lines. Every second sample (50 m apart) was analyzed. Soils were sampled from approximately 50 centimetre-deep holes (B-horizon) and shipped to Intertek Testing Services/Bondar Clegg (AITS@) in Jakarta, Indonesia, for analysis of gold, silver, copper, and zinc. Gold analyses were performed on the fine fraction (-80 mesh) by standard fire assay using a 50 gram charge, with a lower detection limit of 5 parts per billion (ppb). The laboratory, as part of its normal quality-assurance procedures, routinely assays a total of 5 standard, repeat and blank samples per 45 samples analyzed. These assay results varied within normal limits.

Other work included an airborne magnetometer survey (1,160 line km) on 200 m-spaced lines over the entire Tiris CoW, plus detailed 100 m infill lines over the Harimau Prospect. The contractor was Jakarta-based PT World Geoscience Indonesia. Only preliminary data from the 200 m-spaced lines have been received to date. A structural interpretation using satellite synthetic aperture radar (SAR) has been completed by Earth Resource Surveys Inc. (Vancouver), and ground mapping and prospecting are still underway on the project, as are detailed infill investigations. Field work was directed by Ron Avery, P.Geo. (Mindoro=s Exploration Manager), and performed by geologists and exploration crews of PT Handal Srirajasa of Jakarta, Indonesia, Mindoro=s local geological consultant.

Phase 2 exploration has identified three broad gold soil anomalies within the Harimau Prospect: Harimau Selatan, Harimau Barat and Harimau Utara, as well as several others not yet ground-checked.

Soil geochemistry results are based on 1,371 samples that have been analyzed to date. The gold values ranged from less than 5 to 862 ppb and averaged 37 ppb. Duplicate samples were collected at every twentieth site and submitted to ITS under different sample numbers. Results for the 113 duplicates showed considerable variability because of the presence of coarse gold. As described below the amount of gold in the soil samples has apparently been underestimated in the fine-fraction analyses.

The Harimau Selatan anomaly is located on the southern edge of the 1,000 ppb gold stream sediment anomaly. This gold soil anomaly likely represents a different source from the main stream sediment response (greater than 4,000 ppb), which is 1.5 km further north and in several different drainage systems. As defined by the 50 ppb gold contour, the soil anomaly is 1.7 km by 1 km, from which 146 samples range from 5 to 779 ppb gold (average 145 ppb). The greater than 100 ppb area (91 samples) is only slightly smaller, covering 1.5 km by 0.85 km. Geological information, limited to stream beds, indicates the area consists of strongly altered dacitic pyroclastic volcanics. Preliminary interpretations from the SAR and airborne magnetic surveys indicate the anomaly lies on the southern flank of intermediate intrusive rocks.

The overall anomaly shows a close correlation with topographically high ground on a moderately dissected plateau. At least four areas of localized surface mining from the Dutch colonial era, dating from around 1910, were noted in the area. Mining consisted of hydraulic sluicing of near-surface oxide material, and was limited to areas around stream channels representing 3% to 5% of the Harimau Selatan soil anomaly area. The strongest soil anomalies at Harimau Selatan occur several hundred metres from the Dutch mining sites. There is little to no contamination related to these old mining operations that may have affected the soil survey results.

Both the historical Dutch sluicing operations and variability of the fine-fraction soil data indicated the presence of coarse gold within the oxide zone. This was tested by panning the soil from a test site, and by analyzing a line of unsieved soil samples and comparing results with sieved (fine-fraction) samples. A total of 12 grains of visible gold (up to approximately 0.2 mm diameter) were panned from a 1 kilogram soil sample. The high clay content resulting from the intense hydrothermal alteration and weathering likely reduces the amount of gold recoverable by simple panning. Sixty-four soil samples from the test soil line contained from less than 5 to 1,963 ppb gold (1.96 grams per tonne) and averaged 127 ppb for the entire test. For comparison, the fine-fraction (-80 mesh) ranged from 7 to 335 ppb, and averaged 73 ppb gold.

The presence of coarse gold within the oxide zone has therefore been confirmed. Stream bank and old sluicing exposures indicate the oxide zone is at least 30 m thick. If the fine-fraction soil anomaly is indicative of an oxide gold resource, it covers a potentially large area (1.7 km by 1 km) which would probably be amenable to shallow, bulk mining methods. Follow-up to investigate this shallow oxide resource potential is in progress. This includes shallow (1 to 3 m, initially) hand auger drillholes on a wide-spaced grid (400 m by 400 m), infill gridding, soil sampling, and sampling of Dutch workings. Primary mineralization potential at depth will be evaluated at a later date via ground geophysics, leading to drilling if justified.

Located 400 m northwest of Harimau Selatan, this soil anomaly is in the interpreted source area of the strongest stream sediment anomalies (up to 18,450 ppb gold and 17 parts per million silver). From the initial 50 by 200 m-spaced fine-fraction soil samples, the gold anomaly is currently defined by 15 samples, ranging from 2 to 862 ppb (average 171 ppb), with four samples greater than 200 ppb. The anomaly is currently 500 m long, with samples having greater than 50 ppb gold occurring across 400 m (3 adjacent lines). Limited panning (one site) recovered visible gold from the soil. There are no old mining sites in the anomaly area.

Geological information is limited to stream beds where intensely altered (silica-adularia-clay) dacitic pyroclastics are intermittently exposed. Abundant intermediate intrusive float boulders occur in several streams. Airborne magnetics suggests the presence of extensive intermediate dykes and stocks intruding the pyroclastics.

The Harimau Barat prospect is considered high-priority due to the strong stream sediment anomalies draining from the area and the extent and intensity of alteration. It is believed that mineralization is related to the intrusive contact with the pyroclastics. Detailed infill gridding, soil geochemical sampling, and geological surveys are in progress.

Located 250 m northeast of the Harimau Selatan anomaly, the Harimau Utara soil anomaly extends some 1.2 by 0.75 km. Defined by the greater than 50 ppb gold contour, it comprises 65 samples, ranging from 10 to 296 ppb (average 104 ppb, with 31 samples greater than 100 ppb). Harimau Utara also flanks the interpreted intrusive bodies. Strong and extensive alteration exists in both pyroclastic outcrop and float. There are no old surface workings in the area of this anomaly. Only limited follow-up has been undertaken to date.

Continuing Phase 2 work will focus on an initial follow-up of the Harimau Selatan and Harimau Barat soil anomalies. This will consist of detailed infill soil sampling, shallow hand-auger soil sampling, and rock sampling. The Phase 2 program will be completed by the end of November, with final results available in December.

Mindoro is a well-financed, Canadian mineral exploration company focussing on gold and gold-copper exploration in the Asia Pacific region and operates projects in the Philippines, Myanmar and Indonesia. Mindoro has 13,515,000 shares issued and outstanding and working capital of approximately $1,400,000.

Copies of the attached figure may be obtained by contacting Mindoro's office or may be viewed at the Company's website.

The Alberta Stock Exchange has neither approved nor disapproved the information contained herein.

You can view the Next Press Releases item: Thu Jan 28, 1999, Further Encouraging Exploration Results Tiris Project, Sumatra, Indonesia

You can view the Previous Press Releases item: Mon Jul 27, 1998, Tiris Project, Sumatra, Indonesia

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