Gabriel Resources is the owner and operator of Rosia Montana in Romania, a mining site with over 10 million ounces of gold and nearly 50 million ounces of silver.
The project, 80 per cent owned by Gabriel along with the Romanian government, has attracted controversy for its use of cyanide to extract the gold.
The firm has a market capitalisation of more than $2bn and is listed in Toronto.
The agency has been charged with communicating the investment case of the business to the international media as well as the international investment community.
Buchanan senior partner Bobby Morse will lead the account.