TECU® Bronze is an alloy of copper and tin. The original warm reddish-brown colour of TECU® Bronze has a distinctive appearance during natural weathering. During initial weathering a reddish-brown colour develops across the surface in more ‘refined’ manner, to give a more even brown tone to a façade compared with TECU® Brass. Over time, the surface darkens further to a rich dark brown on the façade. On inclined cladding areas, eventual patina formation is significantly slower than that of classic copper, and has a unique appearance.Typical for this alloy is a brown-red oxidation of the surface with browngrey undertones; the material then very gradually changes to dark brown anthracite throughout. The subsequent patina coating forms much more slowly than with traditional copper – and with very singular results.