The Riva Outdoor Stool from Sunpan features glass fiber-reinforced concrete with a decorative marble-effect finish created by hand-applied water-transfer printing. This finishing technique produces unique surface patterns across each stool, with color transitions and veining effects that differ between pieces. The concrete material proves durable for outdoor use, resisting deterioration from UV rays, moisture, and seasonal temperature changes. A protective topcoat sealing prevents staining while maintaining the surface finish, and the concrete develops natural characteristics during curing, adding individual character to each piece.