• Shares of Australia's Aureka rise as much as 19.1% to A$0.125, marking their biggest intraday pct gain since February 25

• Shares hit their highest level since April 13

• Mineral explorer reports high-grade gold and silver findings in two separate zones at its Comstock gold project in Australia

• Says lack of significant sulphides suggests gold can be recovered relatively easily, which will be confirmed with a metallurgical testing programme

• YTD, stock down 20.7%, including session's moves

(Reporting by Subhalakshmi Dey in Bengaluru)