Sapphire production for future Apple products jumped five-fold in April, according to a report from UBS Securities.
The research note (via Barron's) from UBS Securities' Steven Chin on Wednesday is centered on GT Advanced Technologies, which is a sapphire material supplier to Apple. Sapphire is a hard, scratch-resistant material currently used on the iPhone 5S' home button. In theory, it could replace the Gorilla glass that Apple currently uses for its iPhone.
"Our monthly checks found GT had a very successful month of April at its Arizona sapphire fab and estimate it shipped about 1 million two-inch equivalents of sapphire to one of Apple's cover screen suppliers (up 5x from the month of March when it first started production)," the note said.
But Chin seems to be leaning toward the rumored larger future iPhone.
"If it is possibly all for a larger screen 5.5-inch iPhone 6 in November, we estimate monthly shipments to this single Apple cover screen supplier need to reach a level of 10 million two- inch equivalents per month by September to give us more conviction of a successful ramp," he wrote.
Apple signed a deal with GT Advanced Technologies back in November. That deal stipulated that Apple provide GT with $578 million in prepayments "at an Apple facility in Arizona." GT owns and operates the furnaces that produce the sapphire.
In related news, On Tuesday, Apple was granted a patent for embedding displays, including those made from sapphire material, in a LiquidMetal iPhone chassis.
GT Advanced Technologies has yet to reply to a request for comment.