a) The base of colorful metal roofing tile is galvalume or galvanized sheet. The processing of the surface adopts techniques of painting and coloring at high temperature. It is environment-friendly multi-layer composite material as roofage. The processing techniques and surface materials are different from those of colorful stone-coated metal roofing tiles. Any color is available as long as the color sample is offered. b) Compare to the galvanized sheet, galvalume is more durable, heat-resisting, heatproof and anti-corrosion. It is generally believed that steel sheet can guarantee 30 years without being rusted or eroded in various conditions.