"Ferretto" is a word in ENGLISH

A mineral of a steel-gray to black color and metallic luster, occurring crystallized, often in twin crystals shaped like cogwheels …

Native copper sulphide, called also copper glance, and vitreous copper; a mineral of a black color and metallic luster.

A native sulphide of copper, occuring in masses of a dark blue color; -- hence called indigo copper.

A name given to some sulphides, mostly dark-colored, which have a brilliant metallic luster, as the sulphide of copper, called …

A mineral of pale steel-gray color and metallic luster, occurring in isometric crystals, and also massive. It is a sulphide …

A partly reduced copper sulphide, obtained by alternately roasting and melting copper ore in separating the metal from associated iron …

A name given to a number of metallic minerals, sulphides of iron, copper, cobalt, nickel, and tin, of a white …

A mineral of a steel-gray or iron-black color; tin pyrites. It is a sulphide of tin, copper, and iron.

A steel-gray mineral of metallic luster. It is a sulphide of silver and copper.

A blackish lead-gray mineral, closely related to tetrahedrite. It is essentially a sulphide of arsenic and copper.

A sulphide of antimony and copper, with small quantities of other metals. It is a very common ore of copper, …