July 21, 2003

TERTIARY AWAITS ASSAYS FROM FORMER RIO TINTO NICKEL-COPPER PROSPECT IN SWEDEN

• Sulphide Mineralisation Present Over 18.5m Section Of Drill Core At Notträsk
• Priority Ground Follow-Up Planned At Finnish IOCG-Type Prospect
• Finnmark PGM Drilling Inconclusive – Further Work Needed

AIM-listed Tertiary Minerals plc says assays are awaited from initial diamond drilling at its Notträsk project in Sweden, where it is investigating an untested electrical anomaly originally detected by Rio Tinto in a previous exploration campaign. Tertiary has completed its own electromagnetic survey to relocate the anomaly, interpreted to be a zone of sulphide mineralisation within the Notträsk gabbro intrusion and therefore prospective for nickel-copper and possibly platinum group metals (PGM) mineralisation.

In its end-June quarterly, the company says significant sulphide mineralisation was intersected within the target zone from 78.1m to 96.6m down hole. This was predominantly pyrrhotite with minor pentlandite (nickel) and chalcopyrite (copper). Visual estimates indicate an average sulphide content of about 15p.c. over a 4m interval within the target zone, together with narrower sections of up to 30p.c. sulphides.

Assay results are expected in approximately three weeks, the company states.

Meanwhile, as part of its ongoing search for Olympic Dam-style iron oxide-copper-gold (IOCG) deposits in Finland, Tertiary is planning ground follow-up at the Palokiimanselkä prospect in north-east Finland as a matter of priority before committing to drill. This is one of the original eight targets the company acquired last October and lies in an area containing alluvial gold deposits which are mined on a small scale. The source of alluvial gold is unknown, says Tertiary.

Mineralisation at Palokiimanselkä comprises N-S striking quartz-magnetite veins within altered gneiss and was originally discovered in the 1950s by boulder tracing and trenching. At that time, five 200kg samples returned gold values ranging from 1.2g/t to 4.1g/t. Smaller samples assayed up to 10g/t gold.

Aerial magnetic data from Palokiimanselkä shows the mineralisation occurs within a 2km long, N-S trending magnetic anomaly, says Tertiary. This suggests the prospect may be part of a much larger zone of mineralisation, it adds. The company also says it has purchased several additional data sets covering its other IOCG targets in both Finland and Sweden.

Commenting on the company’s PGM project in the Finnmark district of Norway, Tertiary says the three drill holes completed into this ultramafic intrusion returned anomalous PGM values in composite samples and higher anomalous values in narrow sections. The objective was to drill-test an induced polarisation (IP) anomaly associated with PGM-bearing outcrop and extending several hundred metres along strike.

The majority of the anomalous drill samples contained only low levels (approx 1p.c.) of sulphide minerals – the likely cause of the IP anomaly – and no direct correlation between higher sulphide content and higher anomalous PGM values was evident, the company states. Consequently, the factors controlling the location of the PGM mineralisation have not yet been established and further assaying and mineralogical work is needed to complete effective testing of the economic potential of the PGM-bearing intrusion.

PLANNING FUTURE WORK AT GHURAYYAH AS TANTALUM MARKET IMPROVES

Tertiary’s major project is wholly-owned Ghurayyah in Saudi Arabia, believed to be the world’s largest tantalum-niobium deposit. A positive scoping study on the project was completed in the March quarter, since when the company has focused on planning future work programmes, including a preliminary feasibility study.

Encouragingly, the company notes there is further evidence of a continuing recovery in the tantalum market, with leading producer, Australia’s Sons of Gwalia, recently announcing record sales for 2002-03 and inventory reduced to very low levels at the end of last month. That company also said inventories were being reduced across the supply chain and that there is evidence of a tightening supply of material sold on the spot market.

Further Information:

Patrick Cheetham, Executive Chairman Tertiary Minerals plc. Tel: 01625-626203
Ron Marshman/John Greenhalgh, City of London PR Limited. Tel: 020-7628-5518