Example – Enargite, Cu3AsS4
From the Greek έναργής for “distinct,” referring to its cleavage, which is perfect, in contrast to the chemically similar Tennantite, which, however, has no cleavage.
Strukturverfeinerung von Enargit, Cu3AsS4
Adiwidjaja G., Lohn J.
Acta Crystallographica B26 (1970) 1878-1879