U.S. stocks fell deep into the red as a selloff in gold prices pulled the materials sector into a spiral. Gold prices fell to their lowest level since the late-June Brexit vote as the U.S. dollar marched to a two-month high. A selloff in gold prices hit the materials sector hard. Gold companies Barrick Gold (ABX) , Newmont Mining (NEM) - Get Report , Goldcorp (GG) , Randgold Resources (GOLD) - Get Report , and Kingross Gold (KGC) - Get Report were all sharply lower. Sears (SHLD) spiked and was briefly halted on reports that bids for its Craftsman business were due by the end of the month. Potential bidders include Stanley Black & Decker (SWK) - Get Report . The unit could be sold for as much as $2 billion. Alphabet (GOOGL) - Get Report unveiled two new smartphones, the Pixel and larger Pixel XL, at a Google event in San Francisco. The phones, the first designed purely in-house, also feature a personal assistant, similar to iPhone's Siri. TheStreet's Keris Lahiff has details from Wall Street.