GT Advanced Technologies, which makes sapphire glass components for smartphones, filed for bankruptcy on Monday. Sapphire glass is an ultra-strong material, which Apple uses on both the camera lens and fingerprint scanner on the new iPhone. However Apple doesn't, contra to some expectations, use the material for the iPhone's main display. The move caught the market flat-footed, and after the announcement, shares of the company were down 90%. The drop in shares of GT Advanced on Monday has taken the company's market cap from roughly $1.5 billion Friday to about $175 million. At least one analyst that Business Insider ... (full story)