VANCOUVER, BC — February 28 , 2008 — Mirasol Resources Ltd. (TSX-V: MRZ; Frankfurt: M8R) is pleased to announce broad intervals of silver-gold-lead mineralization from channel sampling of the Cerro Plomo prospect at its 100%-owned Libanesa Project, Santa Cruz Province, Argentina.
At Cerro Plomo, a 50 by 50 metre exposure of hydrothermal breccias and fracture veining crops out at the edge of a salt pan (see press release July 27, 2007). Mirasol completed one hundred and thirty meters of backhoe trenches and outcrop channel sampling which partially tested the southern extent of the mineralized outcrop at the edge of the salt pan.
Trenching extended the area of outcropping breccia and showed that while the breccia is closed off in the trenches, it is surrounded by a zone of jarosite (iron oxide) fracture veining in the wall rock that remains open to the south. The trenches carry anomalous values over their full lengths due to the fracture veining (see Table 1). Length-weighted average results for the full length of the trenches include 27.7 metres of 14.5 g/t silver, 0.45 g/t gold and 0.84% lead; 13.35 metres of 52.0 g/t silver, 0.74 g/t gold and 0.85% lead, and 9.65 metres of 151.6 g/t silver, 0.53 g/t gold and 2.13% lead.
Twenty-three select samples of the breccias’ matrix and fracture veins from the Cerro Plomo zone (see Table 2) averaged 325 g/t silver, 0.59 g/t gold and 3.54% lead, with individual samples up to 2830 g/t silver, 2.21 g/t gold and 48.45% lead. This suggests the potential for bonanza grade mineralization where the breccias’ matrix and veining become volumetrically more significant.
|Table 1: Cerro Plomo Breccia – Trench Results|
|Trench||Interval meters||Silver g/t||Gold g/t||Lead %|
|Full length of trench||C_1||13.35||52.0||0.74||0.85|
|Full length of trench||C_2||9.65||151.6||0.53||2.13|
|Full length of trench||T 1||27.7||14.5||0.45||0.84|
|Full length of trench||T 2||19.2||17.0||0.83||1.07|
|Full length of trench||T 3||14.7||15.0||0.53||0.78|
|Full length of trench||T 4||14.3||20.7||0.28||0.81|
|Full length of trench||T 5||13.35||7.1||0.07||0.28|
|Full length of trench||T 6||24||7.7||0.42||0.82|
|Table 2: Select Breccia Matrix and Veinlet–Rock Chip|
|Sample||Interval meters||Silver g/t||Gold g/t||Lead %|
A preliminary petrologic study of the breccia shows a jarosite (iron oxide) matrix with supergene lead and copper minerals, containing clasts of crystalline galena with inclusions and rims of the silver-bearing minerals. This indicates the breccia hosts at least two phases of primary mineralization, the earliest being transported galena as clasts from depth beneath the surface outcrops, and the second occurs as silver sulphides and silver sulphosalt minerals deposited on the galena clasts and in the breccia matrix.
Cerro Plomo is part of a larger silver-gold-lead mineralized zone that is intimately associated with an andesitic dyke swarm with a radial pattern. The mineralization manifests as a series of narrow hydrothermal breccias and sub-metre veins, partially exposed through shallow cover over a one square kilometre area. Mirasol’s mapping and detailed ground magnetic survey suggest a prospective geological and structural setting which may host further concealed mineralization. Mirasol has completed an MMI (mobile metal ion) soil grid over a 1.4 by 1.2 kilometre area, centred on Cerro Plomo, designed to identify additional mineralized zones. Assay results from this survey are pending.
Mirasol’s management is highly encouraged by results received to date from the Libanesa Project. Cerro Plomo represents a quality drill target with the potential for bulk tonnage silver-gold-lead mineralization, and-or for possible bonanza grade mineralization in more restricted bodies. Future drill testing is required to determine if Cerro Plomo is a pipe, or the top of a larger mineralized breccia body. Indications to date suggest that there is good potential to identify further zones of mineralization within the project.
Stephen C. Nano, Vice President of Exploration for Mirasol, is the Qualified Person under NI 43-101 who has prepared and approved the technical content of this news release.
For further information, contact:
Mary L. Little President & CEO
Tel: (604) 602-9989: Fax: (604) 609-9946
Trent Dahl, Ascenta Capital Partners Inc.
Phone: (604) 684-4743 ext. 228
Toll free: 1-866-684-4743 ext. 228
Surface Geochemical Sampling: All assay results reported herein are for rock and stream sediment samples collected from surface; assay results from drill core samples may be higher, lower or similar to results obtained from surface samples.
Quality Assurance/Quality Control: Exploration at Mirasol’s Argentina Projects is supervised by Mirasol’s Exploration Manager, Timothy Heenan and Paul Lhotka, Principal Geologist, both qualified persons under NI 43-101. All technical information for the Company’s projects is obtained and reported under a formal quality assurance and quality control (QA/QC) program. Rock chip and stream sediment samples are collected under the supervision of Company geologists in accordance with standard industry practice. Samples are dispatched via commercial transport to an ISO 9001:2000-accredited laboratory in Mendoza, Argentina for analysis. Results are routinely examined by an independent geochemist to ensure laboratory performance meets required standards.
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