Copper carbonate is a widely used, finely powdered colourant in glass fusing, stained glass, and ceramics, valued for producing vibrant turquoise, blue, and green tones. In fused glass work, it’s commonly placed between layers of clear glass to create decorative effects such as delicate blue bubbles or scattered specks in shades of blue, turquoise, and green.

Blue Bubbles in Fusing: When sandwiched between two layers of glass and fired, copper carbonate breaks down and forms small, vivid turquoise-blue bubbles. It’s often preferred over copper oxide as it’s lighter in composition and produces finer, more evenly distributed bubbles in greater quantity.