John Teeling's Connemara Mining has struck gold in Donegal.
The company announced on Thursday that drilling in one of its Donegal licences in February had led to the discovery of a significant gold bearing vein system in Inishown.
Teeling, the company's chairman perhaps best known as the founder of Cooley Distillery, said:
"The drill results reported today though early stage are promising.
"Multiple gold bearing veins have been intersected with one stretching over 3 metres at a gold grade of 5.8 grams per tonne.
"The discovery is similar to the Dalradian gold resource across the border in County Tyrone".
The Canadian company Dalradian Resources recently discovered a multi-million ounce gold deposit in Curraghinalt in Tyrone.
Following Connemara's announcement, shares in the AIM-listed company have doubled their Friday morning opening price.
They are now trading at 3.35 per share in London.
It is one year since Connemara Mining acquired its five licences in the Inishowen peninsula.
Tellus geochemical field survey data at the time confirmed the presence of elevated gold in the area.
Tellus boarder survey - darker shades indicate areas where gold is more likely to be found
At the time, Teeling said his company was taking an "aggressive stance" in targeting the gold discovery.
Connemara Mining currently holds 35 prospecting licenses in the country.