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Sula Iron & Gold (LON:SULA) said exploration at its 153 sq km Ferensola project in Sierra Leone had confirmed the prospectivity for coltan mineralisation.
The reconnaissance fieldwork for coltan kicked off in September last year and the programme was designed by industry heavyweight consultant SRK.
Coltan is a coarse grained metal ore, from which elements niobium and tantalum are extracted; these are sought-after elements and used in the electronics industry.
The 46 ore samples were screened and panned to a heavy mineral concentrate and analysed at a lab.
Nick Warrell, Sula's chief executive, said: "We are pleased to be rapidly progressing our coltan exploration project since its discovery last year."
"We are excited by the confirmation that there is coltan mineralisation along the streams that flow deeper within the licence area, further proving the high prospectivity of the area.
"This is also positive news as we progress our talks with a potential off-taker for the project."
The results of 46 samples, which are indicative only and do not provide values for in-situ grades, will be used to guide the ongoing pitting programme for coltan, which will provide more quantitative data, the firm said.
Speaking to Proactive, Warrell added that the firm's next target was to get to the drilling stage by the end of the dry season - July.
He confirmed the grades so far were high enough to attract an off-take partner.
"We've got some grades in excess of 3% and the typical industry cut-off grade for coltan is 0.15% to 0.12%."
The upsurge in the price of coltan, which the firm hopes to take advantage of, has been caused by the cutting off of supply from the world's biggest producer, the DRC, added Warrell.
Earlier, the mining firm told investors one sample in the southeast quadrant of the licence area graded more than 3% tantalum and provided strong evidence for the presence of coltan mineralisation in the vicinity.
Other high grade samples were found near the eastern boundary of the licence along streams that flow from deeper within the licence area, suggesting that further alluvial and primary coltan mineralisation may be found in this location.
Sula shares eased 2.27% to 1.075p.