hi guys, I noticed that the rim of my exhaust pipes have a deposit as shown in the picture below... the deposit feels like minerals, and somehow bluish... is that possible that the antifreeze is sipping into the engine? the antifreeze consumption is maybe around a cup per year, which is normal for a BWM as i understand... any other ideas?

Attached Images

 

__________________
BMW X5 3.0si 2008
Premium Package
Light Package
Navigation
Reverse Camera
Rear Sensor (retro-fit)
Comfort Access
Spare Wheel
Power folding mirrors
Voice Control w Bluetooth
Power trunklid

BMW X3 3.0i 2006
M Aerokit
M Sport Package
Navigation System
BT Handsfree
Xenon HID

BMW X5 3.0i 2001 --- SOLD