Note 71 — SCENE III.
Reading edition
——————Can charms Be writ on such pure rubies?] This, I believe, alludes to a very old opinion, that some sorts of gems (from an inherent sanctity) could not be profaned, or applied to the purposes of magic. The notion took its rise probably from some superstitious ideas respecting the precious stones employed in the breastplate of the high-priest of the Jews.—Gifford.