A cyanotype is a photographic printing process that produces a cyan-blue print. It was developed in the mid-19th century and is known for its distinct blue hue. The process involves treating paper with a mixture of iron compounds, which react to UV light to create the cyan-blue color. The artist or photographer places objects or negatives on the treated paper and exposes it to sunlight or UV light. After exposure, the print is washed to halt the chemical reaction, leaving behind a unique blue and white image. Cyanotype prints are prized for their ethereal and dreamy quality, making them a popular choice for artists and photographers seeking a distinctive alternative to traditional black and white prints.