Copper oxide is a black solid substance. It is generally in a fine powder form and has many different applications.
The most common use for this substance is in ceramic applications. It produces the hues and tints that help the pieces of ceramic to become blue, red or green. It is used to help produce the enamels and glazes that make these colors possible. This is the number one use for copper oxide and takes up the majority of the copper oxide that is used in the world. Copper oxide can also be used to help produce the synthetic material rayon.
Less commonly, copper oxide is used as a component of supplements for animals that do not get enough natural copper in their diets. It is used for this less commonly because the side effects of copper oxide are often not worth the benefits that it provides.
When it is in powder form and being used in the production of materials, copper oxide can be detrimental to health. It can affect the kidneys, the central nervous system and the respiratory system. It is also a skin and eye irritant and can cause blindness if left untreated. Large amounts of copper oxide ingested will cause the digestive system to become compromised, and the substance can be fatal when large amounts are used.