24) MERCURY. 1. Octahedron, more or less deeply truncated on the edges. When the truncating planes become so large that the original planes disappear, the 2. Garnet dodecahedron is formed. The edges of this figure are also frequently truncated, and often so deeply, that it passes into the 3. Leucite crystal, or the double eight-sided pyramid, flatly acuminated on both extremities by four planes, which are set on the alternate lateral edges. The crystals are small and very small; usually imbed ded, and sometimes two or three occur adhering together. Externally it is shining and splendent, with a metallic lustre. The fracture is imperfect conchoidal. The fragments are rather blunt-edged. It is soft. When pressed between the fingers, or cut with a knife, it emits a creaking sound like artificial amalgam. It is uncommonly heavy. Second Subspecies, Solid Amalgam. Eestes Amalgam, W^erner. External Characters. _ Its colour is silver-white, which in some varieties falls into reddish-white. It occurs massive and disseminated. It is shining, approaching to glistening, The