The Open Pro is available in four different finishes:

Silver: with an anodised, polished surface.

Black: with a black anodised, polished surface.
Ceramic 2: The sidewalls have been treated with a coating made from titanium and aluminium oxide. Aluminium oxide is the abrasive in wet-or-dry paper, hence it works well as a braking surface.
CD: This is Mavic's extra tough anodisation process, making rims durable.