From the manufacturer:
Toison D'or pencils are the pinnacle of graphite drawing instruments. Encased in California cedar, they can be identified by their black lacquer and cream, gold, and black bands. California cedar is one of the best woods for pencil making because it is a renewable resource that prevents warp-age. The Hardtmuth leads are perfectly centered within the casing to ensure even, clean sharpening, and are glued throughout to prevent breakage. Premium Hardtmuth® graphite is combined with a select mixture of clays and high quality, proprietary binders to create an extra smooth drawing lead that doesn't scratch or snag, regardless of degree.