SOURCE: Oriental Minerals Inc.

June 06, 2007 08:30 ET

Drilling Again Intersects High-Grade Tungsten-Molybdenum Mineralization at Sangdong

VANCOUVER, BC--(Marketwire - June 6, 2007) - Oriental Minerals Inc. (TSX-V: OTL) is very pleased to announce further high-grade tungsten mineralization from the Company's third drill hole at the Sangdong tungsten-molybdenum project in South Korea. Highlights include an 18-metre interval grading 0.58% tungsten oxide (WO3), 0.19% molybdenum sulphide (MoS2), 0.15% bismuth (Bi), 0.21 g/t gold, and 0.01% tin (Sn).

This intersection is approximately 74 metres up-dip from the March 1, 2007 results reporting a 22-metre interval grading 0.87% WO3 intersected in hole SD-01. Within this 22-metre interval is a high-grade zone over 6 metres grading 2.37% WO3 and 0.12% MoS2, with 0.34 g/t gold, 0.02% tin and 0.15% bismuth.

Highly significant tungsten-molybdenum mineralization has now been intersected in drilling continuously over at least 730 metres laterally up-dip to surface. Intersections of the skarn package thus far include:

* 152 metres grading 0.20% WO3, 0.08% MoS2 in SD-01
* 141 metres grading 0.10% WO3, 0.02% MoS2 in SD-03
Visual indications of tungsten-molybdenum mineralization are evident in SD-04 and SD-06 (assay results are pending on these holes). Oriental is now evaluating Sangdong for its potential to be a very large, open pit mining operation.

Background on Hole SD-02

SD-02 was designed to drill test the entire 165-metre thick skarn package approximately 75 metres up-dip from the first hole SD-01. SD-02 was also designed to drill test the potential for up-dip extensions from the historical molybdenum resource hosted within the Jangsan Quartzite below the skarn package. Unfortunately SD-02 was abandoned part way through the mineralized skarn zone after hitting old workings associated with the historical mining of the Hangingwall Vein at 202 metres depth. A wedge off of SD-02 was made at 120 metres in an attempt to penetrate the Hangingwall Vein workings, but this was also abandoned at 180 metres when it too failed to penetrate these workings.

Results from hole SD-02 sampled above the old workings are tabulated below:

------------------------------------------------------------------------
Intersection  Depth    WO3   Mo S2  Sn   Au    Bi       Formation
Thickness             (%)     (%)  (%) (g/t)   (%)
------------------------------------------------------------------------
31 metres    149-178m  0.06  0.01   0.10 0.01 00.0   Sedimentary Breccia
18 metres    178-196m  0.58  0.19   0.02 0.21 0.15   Skarn
             196-202m                                Cut and fill stope.
------------------------------------------------------------------------
The mineralized sedimentary breccia-skarn zone in SD-02 averages 48 metres @ 0.26% WO3, 0.08% MoS2, 0.07% Sn, 0.08% Bi, 0.08 g/t Au, and 5 g/t Ag. This lies above the Hangingwall Vein. The skarn package below the Hangingwall Vein workings in SD-02 has yet to be sampled and so mineralization remains open at depth, including around the Main Vein, also previously mined by Korean Tungsten Co., Ltd.

Within the overlying Pungchon Limestone, several intersections of silver-copper-zinc-gold-bismuth were also recorded, including:

-----------------------------------------------------------
Intersection  Depth   Au(g/t) Ag(g/t) Bi(%)  Cu(%)  Zn(%)
Thickness
-----------------------------------------------------------
1 metre      29-30m   < 0.01   9.4     0.00   0.14   0.00
1 metre      31-32m   < 0.01  16.7     0.00   0.21   0.02
2 metres     38-40m   < 0.01  41.1     0.01   0.51   0.06
3 metres   106-109m     0.09  44.8     0.04   0.10   0.72
1 metre    117-118m   < 0.01  26.3     0.01   0.02   0.10
1 metre    121-122m     0.03  17.8     0.01   0.02   0.10
1 metre    124-125m   < 0.01  21.2     0.01   0.10   0.18
3 metres   127-130m   < 0.01  19.2     0.01   0.07   0.14
1 metre    143-144m   < 0.01  42.9     0.04   0.38   0.01
-----------------------------------------------------------
These intersections confirm the presence of near-surface mineralization associated with structurally controlled carbonate vein breccias and hematite alteration in the Pungchon Limestone, which was previously regarded as waste. Larger structural zones have been recognized by surface mapping and sampling (as reported February 7, 2007) and will be targeted by a specifically designed drill program after Phase II drilling is completed.

SD-02 intersected the following lithological units in sequence:

0-149m. Pungchon Limestone.
149-181m. Basal sedimentary breccia of the Pungchon Limestone.
181-196m. Quartz-scheelite vein stockworks in skarn altered Myobong Slate.
196-202m. Underground workings.
Drilling Program Update

Phase II Drilling has now commenced on the 100 metre x 100m grid spacing drill out of the Sangdong deposit. Holes SD-07 and SD-08 have completed at their targeted 300 metres depth, Hole SD-09 is currently at 275 metres depth, SD-10 at 208 metres depth, SD-11 at 154 metres depth, SD-12 at 243 metres, SD-13 at 117 metres depth and SD-14 at 6 metres depth, with Hole SD-15 about to commence.

Six diamond drill coring rigs are now operational on site, including an Australian-based Longyear 38, together with all ancillary equipment. A large Australian-based track mounted RD1000 Reverse Circulation-Diamond drill rig and track mounted compressor has also arrived on site and is currently setting up. The arrival of the RD1000 Reverse Circulation-Diamond drill rig offers the potential to penetrate the Hangingwall Vein mine workings, rapidly drill through Pungchon Limestone cover, as well as drill much deeper holes to test the Deep Moly historical resource. Abandoned holes SD-02 and SD-05 will be re-drilled using this more capable, higher performance drill rig.

Please click on the following link to view the Sangdong Mine.
http://www.usetdas.com/maps/orientalminerals/sangdong.pdf
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Within the skarn package, the Main Vein was previously mined by the Korean Tungsten Co., Ltd during 1947-1992. Detailed mine plans suggest approximately 30% of the Main Vein was left behind as roof pillar support. A historical resource of the remaining pillars and the unmined boundaries of the 6-metre thick Main Vein was reported by KORES.

Widespread disseminated molybdenum mineralization has been intersected below the skarn package within the Jangsan Quartzite. This mineralization is associated with narrow bedding concordant quartz-molybdenite veins with occasional sub-vertical vein structures. Drill hole SD-01 has confirmed that a major molybdenum mineralized system is clearly present at the Sangdong mine.

Previous underground drilling (22 diamond drill holes) by Korean Tungsten Co., Ltd and KORES discovered the deep molybdenum historical resource beneath the tungsten mine workings.

Note: Samples are 1-metre split HQ core samples and were submitted to ALS Chemex laboratory in Brisbane, Australia and analyzed by Ore Grade Method XRF-ME05, Au-AA21, ME-ICP41s and Ag-OG46. Quality Control: Blanks and Standards samples were routinely inserted with the drill samples at random intervals. Analysis of Standards indicates the laboratory results are all within +/-5% of certified assays and so results are considered reliable. Blank samples were clean, indicating no cross contamination in the samples.

QUALIFIED PERSON

The qualified person for the purposes of this release is Mr. Mark Dugmore.

On behalf of the Board of Directors,
Damien Reynolds
Chairman and Director
Statements in this news release, other than purely historical information, including statements relating to the Company's future plans and objectives or expected results, constitute Forward-looking statements. Such statements are based on numerous assumptions and are subject to all the risks and uncertainties inherent in the Company's business, including risks related to mineral exploration and development. Consequently, actual results may vary materially from those described in the forward-looking statements.

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

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