Mimetite is a lead arsenate with chlorine that crystallizes in the hexagonal system, has a hardness of 31/2-4 and a density of 7.2 g/cm3. The shine is resinous, and the colour is highly variable. It can be colourless, yellow with brown or orange tones, red-orange, grey and white. Usually, the shape of the crystals consists of simple prisms, barrel-shaped and rarely tabular or pyramidal. Sometimes they are observed with stalactitic, reniform, globular and acicular habits. This mineral species has two polymorphs, that is, identical chemical substances that occur in different forms or structures, and these are Mimetite-2M and Mimetite-M.

Its name derives from the Greek word μϊμητής (mïmitís), “imitator”, alluding to its resemblance to pyromorphite.

The mining district of Santa Eulalia has been in almost continuous production for more than three centuries (from 1703 to the present). Spanish pioneers built the city of Chihuahua on the riches that flowed from their mines.