The Black Amber or Jet is a stone found in Whitby, on the Yorkshire coast, in England. It is extracted from the decay of wood or coal and it is used from the construction of statues to the manufacture of jewelry.
In the 19th century, it became popular after being associated with mourning jewelry, but its use can be traced back to Roman times. It was very fashionable in the 1870s and 1880s, when it started to be used to make reliquaries, pendants, brooches and bracelets, being cut in the shape of fruits, flowers and animals.
Bibliography: Allan, Georgina O’Hara; Fashion Encyclopedia: From 1840 to the 1990s: Companhia das Letras, 2010.