Copper and Teal Geometric Panels

Left outdoors, copper can take decades to turn green. Metalworkers who want the color sooner brush or spray the metal with solutions of ammonia, salt or vinegar, which can bring up a deep teal in days. The art is in stopping at the right moment, with some bare copper still glowing through. A wall of panels done this way mixes woven strips, interlocking petals, narrow ribs and plain triangles, so no two squares of the copper patina jigsaw puzzle feel alike.