Emily Dickinson Lexicon

UL-TRA-MA-RINE', n. [supra.]

1. A beautiful and durable sky-blue; a color formed of the mineral called lapis lazuli. According to Gmelin of Tubingen, sulphuret of sodium is the coloring principle of lapis lazuli, to which the color of ultramarine is owing. He has succeeded in preparing artificial ultramarine by heating sulphuret of sodium with a mixture of silicic acid and alumina. An. de Ch.
2. Azure-stone. Ultramarine ashes, a pigment which is the residuum of lapis after the ultramarine has been extracted. Their appearance is that of the ultramarine, a little tinged with red, and diluted with white. Cyc.