Note 3090 — BOOK XXXVII. THE NATURAL HISTORY OF PRECIOUS STONES.

“Pliny has here committed a gross mistake, which has not been observed by Hardouin. Theophrastus, in the passage alluded to, does not speak of a ruby, but the well-known black marble of Chio; though he calls both carbunculus, a name given to the ruby, on account of its likeness to a burning coal, and to the black marble on account of its resemblance to a quenched coal or cinder; and the latter, as well as the Obsidian stone, was sometimes used for mirrors.”—Beckmann, Hist. Inv. Vol. II. pp. 67, 68. Bohn’s Edition.