PEARL.
This substance is easily sawed into shape, and is easily turned with a common steel tool. It is polished readily with pumice stone and water and “putty powder,” this last to be had of chemists or lapidaries. It is better to preserve the colored surface as nature left it, for the beautiful rays and tints presented by it are owing to a peculiar disposition of thin scales on the surface, which retain the light; if these be destroyed, the beauty of the material is lost. It is to be had of marine store keepers generally, or the amateur can get it more readily of the nearest button manufacturer.