By midafternoon, the nano-cap had tumbled 9.7% to 35.5 cents.
Trading volume of 9.4 million shares had exceeded its three-month daily average of 7.8 million.
Since Monday, shares are down 26%.
Earlier in the week, the precious metals producer announced its preliminary first-quarter results. Over the three months to March, underground production averaged around 3,065 tonnes per day. Payable palladium production totaled around 42,500 ounces for the quarter.