[2693] Not the Pyrites of modern Mineralogy, combinations of sulphur with various mineral ores.
[2694] The Greek for “fire” being πῦρ.
[2695] Sulphate of copper, probably, our Chalcopyrite, or yellow copper pyrites.
[2696] See B. v. c. 35.
[2697] Or “quick,” “vivos.” Ajasson identifies these with the quartz agates that form our gun-flints, a Chalcedonic variety of Silica.
[2698] Amadue, or German tinder.
[2699] Fossil shells of oysters and bivalve mollusks, combined, probably, with Fahlunite or Hydrous Iolite.
[2700] This is the most delicate variety of Asbestus, a kind of Hornblende: it presents the lustre of satin. As to Asbestus, see B. xix. c. 4, where Pliny has evidently taken it to be a vegetable production.
[2702] “Earthy” stone. These are either nodules of iron-stone, hollow in the centre, or else round, inorganic masses, hollow, and lined with crystals within. These latter are mostly of a silicious nature.