The drilling completed the three initial projects funded by Fortuna Silver Mines' (US:FSM) US$1.2 million strategic investment announced in April 2017 to test Prospero CEO Tawn Albinson's blind discoveries hypothesis.
"Although the current drill programme is limited to 3 holes, we've cut new vein systems within 25km of one of the world's great silver-gold districts, the Pachuca-Real Del Monte system, which produced over 1.2 billion ounces of silver," Albinson said.
"The intercepts, which include 1.35m at 227g/t silver between 147.4m and 148.8m in hole 1, demonstrate that the negligible silver and gold anomalies we noted in the surface alteration are related to a potentially significant epithermal vein system at depth."
Additional samples are being processed and the company said more drilling was warranted.
Prospero had C$1.67 million (US$1.29 million) in working capital at the end of September.
Fortuna has the right to select one of Prospero's projects for a joint venture and can earn a staged 70% interest by spending US$8 million over six years and completing a preliminary economic analysis.
Prospero shares have ranged between C10-34c and last traded at 13.5c, capitalising it at $4.1 million.