M-I SWACO is the leading supplier of drilling fluid systems, engineered to improve drilling performance, and as such is a vital part of the world’s hydrocarbon exploration and production industry. The company, which has an office in Aberfeldy and operates the nearby Foss mine, employs 10,000 people in more than 75 countries. In August 2010 M-I SWACO became part of Schlumberger, the world’s largest oilfield services company. This employs approximately 126,000 people representing more than 140 nationalities working in more than 85 countries. The primary driver of this merger was drilling optimization. In order to sustain and increase world oil and gas production higher levels of drilling will be necessary in increasingly challenging and complex environments. Further information at M-I SWACO . M-I SWACO milling operation in Aberdeen Mining barite at the M-I SWACO Foss mine. Major oilfield services company M-I SWACO plans to develop a underground barite mine at Duntanlich, near Aberfeldy, in Perthshire. M-I SWACO is the leading supplier of drilling fluid systems, engineered to improve drilling performance and in August 2010 became part of Schlumberger, the world’s largest oilfield services company. Exciting new Barite mine at Duntanlich in Perthshire.