Found this from an official BMW press release regarding frozen paints.
"About BMW Individual Frozen Paint Colors.
The special BMW Individual matte paintwork on the M3 Competition Edition adds a rare metallic luster to the vehicle. Compared to conventional exterior colors with gloss finish, the sculpture-like character of the Frozen Silver paint highlights the athletic contours of the M3. To achieve this luster, a special BMW-developed silk matte clear coat is applied over the Silver Metallic base coat. BMW Individual’s Frozen paints meet or exceed all BMW standards for durability and longevity, and feature a full factory warranty. Special care guidelines are provided to customers and authorized BMW centers to prevent the finish from becoming glossy."