South Boulder Mines Eyes Key Feasibility Studies for Colluli Potassium Sulphate

Development News
South Boulder's Colluli project is located in close proximity to the coast, with Hong Kong based KLID on the lookout for a binding off take agreemen
South Boulder’s Colluli project is located in close proximity to the coast, with Hong Kong based KLID on the lookout for a binding off take agreement

By Proactive Investors,

SOUTH Boulder Mines (ASX: STB) continues to advance its Colluli Potash Project in Eritrea which is a large, high grade potassium bearing resource close to surface in an emerging potash province.

Key feasibility studies will be released in 2015 providing further detail and progression on development options.

At Colluli over 1 billion tonnes of potassium bearing salts have been defined, which are suitable for the production of potash fertilisers

It is one of only three major deposits containing kainite salt (key salt for SOP production) in solid form globally. 

The joint venture with the Eritrean National Mining Company (ENAMCO) is a key plank for project success.

Recently a strategic share placement to Kam Lung Investment Development Company (KLID) was completed at a premium, with KLID holding an option for a further purchase of shares upon securing a binding offtake agreement for potassium sulphate.

Key advantages of the project are its close proximity to coast, while being located geographically favourable relative to key markets.

Its shallow mineralisation supports Colluli as open pit – a proven, safer mining method, with better overall resource recovery than underground and solution mining,

Colluli hosts a highly-favourably suite of potassium bearing salts for low cost production of potassium sulphate (SOP or sulphate of potash) using simple mineral processing units (flotation and mixing).

Commercial grade SOP has already been produced from a Colluli sample.

Other drawcards for Colluli are its large 1 billion tonne resource, its modular approach to development and the company’s relationship with the Eritrea Government.

South Boulder and the Eritrean National Mining Company (ENAMCO) are equal shareholders of the Colluli Mining Share Company (CMSC) which will develop the Colluli Potash project.

Potash demand drivers include:

  • Increasing global population +80 million people annually;
  • Decreasing arable land; and
  • Changing dietary preferences.


SOP is a high value potash fertiliser, which provides both potassium and sulphur in soluble forms.

It has a lower alt index than MOP (no chloride), and is suitable for chloride sensitive crops such as fruit, berries, vines, nuts, coffee and tobacco.

SOP is ideal for arid areas where chlorides cannot be washed away, and is used when soil or irrigation water salt levels are high and MOP is undesirable.


– No communities within the exploration tenements.
– Process can accommodate seawater – consistent and unlimited water supply to be piped from the Red Sea coast to the Colluli site. No major abstraction from local aquifer.
– Unsealed coastal road runs within 60km of the Colluli site.
– Simple logistics for minesite consumables (only 180km from Massawa port).
– No clearing required.
– Ease of access for construction equipment and mining fleet.


South Boulder has also adopted a modular development philosophy offering expandability rather than a single large scale development.

This has the impact of reducing capital risks; optimising processes; better capital management; and ease of Expandability.

Its infrastructure solution is also based on modularity, simplifying logistics and reducing earthworks.


The completed strategic share placement to KLID at a premium has an option for further purchase upon securing a binding offtake agreement for potassium sulphate.

The deal also gives KLID the option to buy an additional 8 million shares, exercisable at $0.35 cents upon securing a binding offtake deal for potassium sulphate on commercial terms acceptable to the CMSC board.


– Final metallurgical report and associated mass balances.
– Completion of mining study.
– Finalisation of resource review.
– Initiation of pilot plant for DFS.
– DFS drilling and completion of hydrogeology work.
– Aggregation of operating and capital costs.
– Submission of second tranche of environmental submissions.
– Finalisation of the pre-feasibility study and lock in module size.
– Commencement of funding discussions.

With Pre-feasibility completion is planned for February 2015 and DFS by mid 2015, there are significant milestones ahead and price catalysts.

South Boulder is well funded with cash at hand of $10.2 million as at 30 September 2014.

Major shareholders include Sprott Asset Management with 10.96% and Kam Lung Investment Development with 7.17%.

South Boulder management hold around 13%.