A spike in put option buying on the Pan American Silver Corp (PAAS) December 20th $15 put options resulted in over 6,000 options trading hands against an open interest of 176—a 34-fold surge in volume.

With shares trading at $16.30, the option bet will move in-the-money if shares drop just $1.30, or about 8 percent. Given the volatility in metals markets, such a swing is easily achievable within the next 52 days before expiration.

At a price of $0.55, the option buyer needs shares to move to about $14.50 before profiting. Based on the company’s 52-week range, shares could drop as low as $10 on a bearish outlook for silver.