Latest reports claim that Apple has procured 518 furnaces to make 100-200 million sapphire glass iPhone 6 screens and has 420 equipment on order as well. 9to5Mac reports that Apple’s manufacturing partner GT Advanced is preparing to manufacture sapphire-crystal displays for future iPhones, with import/export documents as proof.

According to the import records GT Advanced has ordered the sapphire crystal inspection machines labeled Intego Sirius Sapphire Display Inspection Tools designed specifically for display-grade components to ensure that the sapphire crystal displays meet high-quality standards, are large enough to process several slabs of screen covers simultaneously.

The documents read: “GT Advanced Technologies is working with key downstream technology providers to optimize fabrication processes and technologies to lower the cost of sapphire cover screen material. SIRIUS Slab automated sapphire inspection tool begins a new level of repeatability and performance throughput to the production of sapphire material intended for high volume markets such as mobile and touch screen devices.”

The company has ordered a number of factory parts such as furnaces and chambers that can turn raw sapphire into boules for re-processing them. GT Advanced has also ordered over 100 tons of graphite.

Apple partnered with GT Advanced last year, to open a manufacturing facility, related to sapphire crystal components, in Mesa, Arizona. With the recent SEC filing, it was clear that the facility will be used exclusively for manufacturing Apple-related consumer products. With the 518 machines purchased, GT could build 103 million and 116 million 5-inch displays per year, and 420 machines on order will add 84 million to 94 million screen covers to the output.