Apple has a secret iPhone in its labs. Documents from the Federal Communications Commission unearthed on Friday show the company designed and developed a gold version of the iPhone X, the $999 smartphone that launched in November 2017 with a 5.8-inch screen and face recognition. The documents appear to have been prepared in July 2017 and submitted two months later.

The design, as reported by MacRumors, shows some decisions that distinguish it from the official color options of space grey and white. Where those two use a stainless steel frame that matches colors seen on the Apple Watch already, the gold version appears to use a new frame not seen elsewhere yet. While the 8 and 8 Plus announced at the same time comes in four frame-matched colors including gold, the use of aluminum may have potentially simplified the changes to the point where Apple pulled the X’s option due to issues changing the steel color.

Apple's gold iPhone X.
Apple's gold iPhone X.

It’s possible that Apple launches the gold iPhone at a later date. The company launched a red iPhone 8 last week as part of its “(Product)Red” lineup. The initiative started in 2006 with the red iPod Nano after U2 frontman Bono teamed up with Apple’s then-CEO Steve Jobs to support the charity initiative. Apple has donated over $160 million to the organization to fight HIV in Africa.

Apple has struggled with color options on devices before, sometimes choosing to delay launches to maintain its reputation for high attention to detail. The company delayed the launch of the white iPhone 4, leaving black as the only option when it launched in June 2010. When it finally arrived nine months later, Apple senior vice president Phil Schiller explained that the company needed to ensure the white glass was thick enough to protect from ultraviolet rays. However, Pocket Lint noted that early white models used mismatching shades for the plastic home button and glass.

If Apple is planning a gold iPhone X, it could choose to announce it at an upcoming event. The company’s annual Worldwide Developers’ Conference, scheduled to start this year on June 4, has gradually turned into a hardware showcase ever since Apple used its keynote speech in 2008 to unveil the iPhone 3G.

If it gets gold right, it could benefit future phones as part of the company’s coming plans for the iPhone.