Photos posted on the Chinese microblogging site Sina Weibo show a new Samsung device said to be the "Galaxy Alpha." The leaker says (through translation) that the device is made of metal with a 4.7-inch screen and a "flagship S5 configuration," which presumably means it has the same specs as the Galaxy S5.
The leaker also says that the back is still removable, and pictures show the typical fingernail slot to peel away the back panel. Presumably the removable back means only the sides are metal, with the back being plastic.
A high-powered 4.7-inch device made out of metal sounds a lot like Samsung's preemptive strike against the iPhone 6, which is rumored to have the same size screen. 4.7 inches would put the Galaxy Alpha at the smaller end of the Samsung spectrum, though the top and bottom bezels means the device itself won't be quite that compact.