In a shocking and sudden turn of events, GT Advanced Technologies, a parts supplier for Apple, filed for bankruptcy on Monday. GT Advanced filed for Chapter 11 in Bankruptcy Court in Manchester, New Hampshire. The glass manufacturer, whose fortunes looked bright only a few months ago, listed assets of $1.5 billion and liabilities of $1.3 billion.

in November of 2013, Apple had signed a deal to make a prepayment of about $578 million to GT Advanced for the construction of new furnaces. These were to make the synthetic sapphire for iPhone glass. However, when Apple introduced new iPhones last month, the smartphones didn’t include the material. Raymond James analyst Pavel Molchanov said the lack of sapphire in the new iPhones was emblematic of the fact that “something very fundamentally broke down in the relationship between Apple and GT Advanced”.

As a direct result, stock in GT Advanced fell more than 90 per cent to 75 cents, wiping out nearly all of its market worth. The company was worth more than $2.8 billion in early July.

Pierre Maccagno, an analyst with Dougherty & Co, who recommended investors sell GT Advanced’s stock after the iPhone announcement, said the company’s file for bankruptcy exposed that GT Advanced had become overly dependent on Apple.

Maccagno said the cost for producing the sapphire material may have been too high for Apple, or GT Advanced may not have been able to produce enough to meet Apple’s needs.

GT Advanced, which is set to have its sapphire included in the Apple Watch going on sale in 2015, is due to begin repaying Apple for its loan starting next year. However, while GT gave Apple an exclusive license for certain applications of its sapphire glass technology, the iPad maker has no obligation to buy the glass, according to the filings.

GT Advanced said it plans to continue operations during reorganization. However, both Apple and GT representatives did not return calls seeking comments or further information.