magician-float-rise-levitation-3GT 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, contrary 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 on Monday has taken the company’s market cap from roughly $1.5 billion Friday to about $175 million. At least one analyst Business Insider heard from after the announcement sees one possible reason for the sudden change from GT Advanced: Apple pulled the plug. Jeffrey Osborne, an analyst with Cowen & Co., wrote that Apple, which lent GT $578 million as part of a supply agreement last November, “had the ability to call the interest free loan back and it appears they have done that.” Last November, GT and Apple entered a multiyear sapphire materials agreement that would include GT manufacturing sapphire materials at an Apple facility in Arizona. That agreement said that GT would reimburse Apple over five years, starting in 2015. More