Brochantite is a sulfate mineral, one of a number of cupric sulfates. Its formed in arid climates or in rapidly oxidizing copper sulfide deposits.

Crystals of brochantite can range from emerald green to black-green to blue-green, and can be acicular or prismatic. Brochantite is often associated with minerals such as malachite, azurite, and chrysocolla, and may form pseudomorphs with these minerals.

Brochantite is a common corrosion product on bronze sculptures located in urban areas, where atmospheric sulfur dioxide (a common pollutant) is present.