The Egyptian Book of the dead by P. Le Page Renouf and Edouard Naville

1. ⁂⁂⁂, a mineral which has not yet been determined. Brugsch

calls it “Opal.” Lepsius thought its colour was blue. Dr. Budge translates “mother-of-emerald.” Renouf’s translation is “green Felspar” (see Chapter 29B, note).