By David Russell, reporter at OptionMonsterNEW YORK -- Ivanhoe Mines ( IVN) saw bullish option activity on Friday for the second time in less than a week. OptionMonster's tracking programs detected the purchase of 2,400 September 9 calls for $1.50 and the sale of an equal number of September 13 calls for 25 cents. Volume was more than quadruple the previous open interest in both strikes, indicating that this is new activity. Owning calls locks in the entry price for buying stock, while selling them at a higher strike helps offset the cost of the purchase but obligates the trader to dispose of shares at a specified level. In the case of Friday's trade, the stock can be purchased for $9 and must be sold for $13. The trader paid a net $1.25 for that $4 bullish call spread, which represents a profit of 220% if the stock closes at $13 on expiration. Ivanhoe's shares fell 4.24% to $9.26 in the session. The stock has been getting killed along with all the other gold miners and is near its lowest price in almost three years. Overall option volume was more than triple the daily average, with calls outnumbering puts by 33 to 1. On Monday of last week, Ivanhoe attracted straight buying in the September 10 calls as investors positioned for a rally. Russell has no positions in IVN.