Roy Bichan, 53, of Colwyn Bay, Clwyd, walked free from court at the end of a trial which has lasted almost a year. But a businessman, John Clarke, 49, of Gerrards Cross, Bucks, said to be involved in what was described as "a latter day gold rush" was found guilty on fraud charges.
The idea behind the share issue in Butte Mining plc in April 1988 was to re-open mining operations for gold, silver and zinc in Butte, North Montana.
The British company claimed that while the mines' former American owners had ceased operations in the 1970s, it could still be a profitable enterprise.
The Crown, however, argued that the value of the metals was deliberately inflated and that a false prospectus was given to potential investors when the shares were launched.
The jury is continuing its consideration of verdicts on Kenneth Malcolm Clewes, 48, a former executive of a mining consultancy and several mining companies, and Clive Smith, 50.Reuse content