South Boulder Mines (ASX:STB) non-executive chairman Seamus...

South Boulder Mines (ASX:STB) non-executive chairman Seamus Cornelius has increased its indirect interests in the company through an on-market purchase.

Indirect interests of Cornelius acquired 100,000 shares in the company for $18,180, or an average of $0.18 per share.

This increases his total direct and indirect interests to 5,442,799 shares.

He also holds 2 million unlisted options exercisable at $0.34 each that expire on 29 November 2016 and 1.5 million unlisted options exercisable at $0.278 that expire on 17 November 2017.

Earlier this month, the company commenced pilot testing of the Colluli process design at the Saskatchewan Research Council in Saskatoon, Canada.

The Colluli Potash Project in Eritrea now 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 Colluli salts at the Saskatchewan Resource Council.

SOP achieves a substantial price premium over the more common potassium chloride.