Serial exploration entrepreneur John Teeling has quit as non-executive director of Minco, the precious metals group he helped to set up, to focus on the interests of one of his other exploration companies.

Until 2004, Dr Teeling was chairman of Minco, which has licences to search for silver in Mexico and more recently zinc in Ireland.

Dr Teeling said yesterday he was not a man to hold the position of non-executive director and preferred to play a more active role in his other interests. He plans, in particular, to focus on Connemara Mining, a private company he set up two years ago following his resignation as chairman of Minco. The company also has licences to search for zinc in Limerick alongside Minco's licence.

"At the time Minco was concentrating on Mexico and I needed to be part of something with an Irish base," he said. "That's why we set up Connemara Mining to focus on zinc in Ireland."

Dr Teeling said he believed now was the right time to mine for zinc and the prospects for both Connemara Mining and Minco were very positive. Demand for zinc, which is used to strengthen other metals and in homebuilding, has risen in recent times as supplies have declined and Dr Teeling estimates demand will continue to grow at about 3 or 4 per cent a year. It currently sells at about $1,800 a tonne, compared with $950 a tonne two years ago.

Jim Finn, former finance director of Minco, also resigned as a non-executive director to focus on the new company. He, Dr Teeling and several members of the Teeling family still have substantial shareholdings in Minco.

As well as Minco and Connemara Mining, a private company, Dr Teeling has set up several other exploration groups, including Petrel Resources, which was recently awarded a licence to drill for oil in Iraq; Pan Andean Resources, which drills for oil in the US; Persian Gold and African Diamonds.

In October Dr Teeling resigned as chairman of another exploration group, African Gold. He is also chairman of Irish whiskey company Cooley Distillery.