On GFXBench portal appeared new device made by Xiaomi with codename Chiron. We don't know from which series will be this phone, especially if we will take a look on its specification.
Xiaomi Chiron will have 5,6-inch display with FullHD resolution and 16.5:9 aspect ratio, which proves that this phone probably won't be next phone from Mi Mix series because previous phone from this series had display with 17:9 aspect ratio, and Mi Mix 2 according to the newest rumors will have 18:9 aspect ratio of the screen. We're sure that Chiron will have 6GB of RAM, 256GB of internal storage and Qualcomm Snapdragon 835 processor - it's the reason why probably under this name doesn't hide Mi Note 3, which will have Qualcomm Snapdragon 660 unit. Moving on, Chiron will have 5mpx front camera and 12mpx camera on back, but there is a chance that new Xiaomi’s device will have dual camera setup on back.
Considering all this information it looks like that Xiaomi Chiron is the upgraded version of Xiaomi Mi6 or it's Xiaomi Mi6c, but for confirmation we will have to wait for upcoming Xiaomi's conferences.