New iPhone 6s Color
The iPhone 6 colors include gold, silver and space gray. The iPhone 6s colors may expand to include a rose gold iPhone 6s color option.
If this happens, expect that it will match the rose gold color of the Apple Watch Edition. It is not clear if a rose gold iPhone 6s would be part of a premium line that uses the special gold that is twice as hard as standard gold.
Kuo only mentions that a rose gold iPhone 6s color is a possibility.