Key points
- Solwara 10 sits within Nautilus’s 100-per-cent-owned exploration licence EL1383, about 24 kilometres southwest of the Solwara 2 prospect in PNG territorial waters.
- ROV mapping and grab sampling outlined an SMS system approximately 680 metres long with an across-strike width of 30 to 270 metres, averaging 110 metres, at about 2,240 metres water depth.
- Thirteen surface grab samples analyzed by hand-held XRF averaged 5.3 per cent copper and 11.5 per cent zinc, with individual samples reaching up to 16.3 per cent copper and 41 per cent zinc.
- Samples have been sent to ALS laboratories in Brisbane for formal base and precious metal assay.
Nautilus Minerals Inc. has discovered a new high-grade sea floor massive sulphide system — Solwara 10.
Stephen Rogers, Nautilus’s chief executive officer, commented: “The discovery of the Solwara 10 SMS system reinforces the prospectivity of Nautilus’s extensive tenements within PNG, demonstrating our ability to pinpoint targets and make discoveries in a short time span. It is very encouraging that we can report this success early in our 2008 exploration program. It also bodes well for our other targets which are being investigated over the coming months in Papua New Guinea and Tonga.”
Mapping along lines nominally 100 metres apart, using a T 200 remotely operated vehicle, has outlined an exposed SMS system, (see the table), containing copper (up to 16.3 per cent) and zinc (up to 41 per cent) by mineralization, as outlined using a hand-held X-ray florescence (i) instrument.
Solwara 10 is located on Manus spreading centre within a 100-per-cent-owned Nautilus exploration licence (EL1383), about 24 kilometres southwest of Nautilus’s Solwara 2 prospect, in the territorial waters of PNG.
Sulphide mineralization at Solwara 10 was mapped visually and confirmed by grab sampling. The SMS system outlined is approximately 680 metres long, by an across strike outcrop width of 30 to 270 metres, averaging 110 metres. It lies on the sea floor approximately 2,240 metres below sea level, on the south flank of a small rise. The SMS outcrop is surrounded by unconsolidated sediment and volcanic outcrops.
Thirteen surface grab samples recovered from the prospect averaged 5.3 per cent copper and 11.5 per cent zinc when analyzed using a hand-held XRF instrument (Niton XLT 592). Samples from Solwara 10 have been dispatched to ALS laboratories in Brisbane for base and precious metal analysis.
SOLWARA 10 INDICATIVE AVERAGE OF
ANALYSES USING HAND-HELD XRF
Sample
No. Cu% Zn% Pb% Description
20007 0.8 41.2 0.4 Massive sulphide
20008 0.9 28.1 0.1 Massive sulphide
20009 12.5 1.2 bdl Semi-massive sulphide
20014 12.4 1.1 bdl Semi-massive sulphide
20015 2.0 20.5 bdl Massive sulphide
20016 2.0 7.7 bdl Semi-massive sulphide
20017 7.2 6.8 bdl Semi-massive sulphide
20018 3.1 25.7 bdl Massive sulphide
20020 16.3 1.2 0.0 Massive sulphide
20021 9.8 bdl bdl Semi-massive sulphide
20022 0.4 7.0 1.7 Semi-massive sulphide
20023 0.3 bdl bdl Sulphate-rich rock
20028 0.6 8.7 0.2 Semi-massive sulphide
Average 5.2 11.5 0.2
bdl equals below detection level.
Co-ordinates projected as UTM zone 56 south using
a WGS 1984 datum.
The Solwara 10 discovery results from deliberate targeting of a water geochemical plume anomaly generated earlier in 2008 as part of the DEA surveyor program.
Pieces of sulphide rubble averaging 17.4 kilograms (from 0.5 kilogram to 70 kilograms) were collected from the sea floor using a manipulator arm mounted on the ROV. Samples were either placed in a sample basket or box on the front of the ROV, where they were then processed on board the ship. Sample selection targeted material that was considered representative of the SMS system. Representative subsamples averaging 6.38 kilograms (from 0.5 kilogram to 15 kilograms), were taken from each of these larger samples using a small jackhammer. The remaining portions of each sample were retained for reference purposes.
(i) Note on results of indicative analyses from hand-held XRF, Niton XLT 592 instrument: A hand-held XRF instrument (Niton XLT 592) was used to obtain indications of the grade of materials recovered from the sea floor. The instrument used for this application does not provide the accuracy required to report assays. These analyses are the mean of 10-to-20-point measurements on unprepared wet surfaces of each of the samples reported. The samples were broken up with a small jackhammer to produce a fresh surface prior to XRF measurement. The instrument is not calibrated using certified standards and the samples have not been crushed and prepared to minimize matrix effects which may affect the accuracy of the analysis. However, previous comparison of results to date with assay data for surface samples indicates the XRF tool is a reliable method for providing indicative results of the tenor of mineralization and providing data for real-time decisions in the field.
Measurements by hand-held XRF are not assay results and do not measure gold or silver. Samples will be formally assayed by the ALS Group in Brisbane.
Qualified person
The exploration results reported in this announcement have been compiled under the supervision of Anthony O’Sullivan, chief operating officer of Nautilus. Mr. O’Sullivan is a member of the Australasian Institute of Mining and Metallurgy, has 20 years experience in mining and exploration geology, and is a qualified person as defined under National Instrument 43-101. He consents to his name being used in this release.
