American depositary receipts of Scorpio Gold more than doubled before being halted in their second day trading on Nasdaq.
The ADRs last traded 130% higher, at US$11.66.
Earlier Wednesday, Scorpio Gold reported favorable results from the Phase Two drill program at the Manhattan District Project in Nevada.
"Manhattan keeps delivering on the two things that matter most in this market: scale and grade," the Vancouver, British Columbia, company said.
The company's TSX Venture Exchange-listed shares were up 21%, to 43 Canadian cents, at the time of a Canadian trading halt. Meanwhile, Scorpio's OTCQB-listed shares rose 54%, to 37 U.S. cents, before they were halted.