GottaBeMobile claims that the photographs came straight from a Chinese factory, and were send from a "trusted source inside the Apple supply chain". It has also published purported photos of the iPad mini.
The images show a metal block used for sample purposes, which reveals the size and shape of the iPhone as well as the positioning of the antenna, ports and buttons.
Overall, the general design of the pictured sample is similar to that of the iPhone 4S, but has a larger display and is just over 5mm taller than the iPhone 4S, at 120mm tall. It has roughly the same width as the iPhone 4S at 58.6mm wide.
If the sample is legitimate, the sixth-generation iPhone could see the introduction of a rear-facing microphone between the camera and the flash. Ridges in the back of the device also indicate that the rumours of a metal back for the iPhone could be true.
It is not yet clear what Apple will name its next generation iPhone, but many people believe that the company will use the same conventions as the new iPad and scrap the number system all together. Apple did, however, win control of the iPhone5.com domain in May.
This story, "iPhone 5 engineering sample leaked" was originally published by Macworld U.K..