Note 1 — Chapter I · THE NATURE OF THE MINERALS AND THEIR MODE OF OCCURRENCE
Reading edition
Chalcopyrite, or Copper pyrites, is a mixed sulphide of iron and copper, of the approximate formula CuFeS₂.
[2] For the history of the name Tungsten, see under the mineral Cerite, Ch. II.
[3] The history of these names will be found somewhat more fully under Gadolinite, Ch. II.