Photographs of what is claimed to be a back panel belonging to Apple's rumoured low-cost iPhone have surfaced online, showing a device with a curved design and a Lighting port.

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The photos, highlighted by Chinese site Apple.pro (Google Translate), show a black, plastic back casing allegedly destined for a budget model of Apple's iPhone. The rear panel looks thicker than the iPhone 5, with a curved design more closely resembling the iPhone 3GS.

Also shown in the photographs is a Lightning connector on the bottom of the casing, but this is the only real link to Apple present in the images. Therefore, the authenticity of these images is (quite clearly) questionable.

The images go against an earlier rumour that suggested that Apple's cheaper iPhone will be available in a variety of colours, but that black will not be one of the options.

However, the timing of the photographs coincides with the rumoured trial production of the cheaper iPhone, which is believed to be beginning this month in preparation for a September launch.

Last week, it was reported that Pegatron will be the sole manufacturer of Apple's low-cost iPhone, following production issues that took place at Foxconn factories during the rollout of the iPhone 5.

These photographs are not the first to have shown up online allegedly showing a cheaper iPhone. In April, a report claimed to show leaked photos, price and launch date of the budget iPhone.

See also:

Apple CEO: We may sell multiple iPhone models in the future

Leaked parts allegedly belonging to Apple's low-cost iPhone shown in new photos

'Apple should make cheaper iPhone' say former CEO John Sculley

Does Apple really need to make a cheaper iPhone for China and India?