Historical studies within the Blue Horizon licence area have proved the existence of Coltan within the alluvial system. To gather an understanding of the coltan’s distribution within the licence, an initial reconnaissance survey is planned. The map on the right outlines the areas of interest (“AOI”) within the licence that will be initially explored in detail AOI 1 and AOI 2.

On 26 November 2014 Sula raised £600,000 through the issue of new shares for the purpose of accelerating its coltan programme. Conditional upon a positive outcome of the company’s ongoing coltan exploration programme, Sula will consider commissioning a small pilot plant to process a number of bulk samples from the Ferensola Project.

SRK ES have reported that “Pegmatites have been observed in the southeast of the licence and are anticipated to be the source of coltan mineralisation; the pegmatites have not been seen elsewhere in the field but evidence of them is presented by coltan in artisanal float across the licence.”


Coltan is mined for its tantalum and niobium elements. There is a very high demand for coltan from the Technology Industry as tantalum is a key element used in the manufacture of capacitors, which are used in almost all electronic circuit boards.

Historically the Democratic Republic of the Congo has been one of the biggest suppliers of low cost coltan to the market giving it the reputation of being a ‘Conflict Mineral’. Recent legislation passed in the US and Europe (The Dodd-Frank Act, 2010) aimed at eliminating the trade in conflict minerals, such as Tantalum and Niobium, requires that end users must be able to show that the minerals from which they were derived have been sourced from conflict-free areas. This has caused a spike in the supply and demand chain, and pushed up the price of coltan in the market.

Sierra Leone complies fully with this legislation, and currently two of the biggest coltan off-takers are actively looking at Sierra Leone as a potential source. Similarly, several Chinese Exploration companies exploring for iron ore in Sierra Leone are also exploring for coltan deposits, as the geology of the region contains coltan bearing pegmatites.

Further, the exploration costs for coltan are relatively low and fairly straightforward because it is coarse grained and tends to be located close to the surface. Establishing a suitable resource generally requires minimal stripping and systematically recorded manual pitting.


Columbite-Tantalite also known as “Coltan” is a dull black metallic ore from which the elements niobium and tantalum are extracted. The niobium-dominant mineral in coltan is called columbite, and the tantalum-dominant mineral is called tantalite. The primary source of this mineralisation is within pegmatites which are proximal to magmatic bodies (usually granitic in composition). These pegmatites are much more prone to weathering than the host granitic bodies or hosting country rocks that they are intruded into, causing the coltan mineralisation to be liberated into the soil horizon and alluvial system. Due to the high density of coltan, around 8g/cm3 it remains relatively proximal to its source within the alluvial system.


Niobium is primarily used in steel manufacture and for superalloys in the aerospace and electronics industries. It considerably increases the strength of steel and its temperature stability makes it ideal for making superconductor alloys for jet and rocket engines and superconductor magnets for MRI scanners.

Niobium prices are historical very stable and are demand-inelastic, with the 2009 slump in demand from the global steel industry having only minimal impact on pricing. Demand is driven by two sets of factors. The first, overall growth in the global economy influencing the demand for steel, and the second, the demand for aerospace superalloys – which are its largest non-steel market.


Tantalum is a heat-resistant powder that can hold a high electrical charge. These properties make it a vital element in creating capacitors, the electronic elements that control current flow inside miniature circuit boards and are used across the technology sector, most notably in almost all cell phones, laptops, pagers, sound systems and computers.

The electronics industry accounts for 50-60% of tantalum consumption, with superalloys the other major end-user at around 20%. The two main mechanisms for its pricing are long term contracts with conventional miners, and spot sales for material from artisinal mines and elsewhere. The spot price movements can be dramatic, tending to range between $100/kg – $250/kg, and have spiked as high as $400/kg during the last technology boom.

Areas of Interest for Coltan Exploration