Trevali intersects high-grade zinc 240 metres below Perkoa Mine https://www.globenewswire.com/news-release/2018/06/05/1516929/0/en/Trevali-intersects-high-grade-zinc-240-metres-below-Perkoa-Mine.html June 05, 2018 08:07 ET | Source: Trevali Mining Corporation