The Chinese word for crystal, _ching_, was originally represented by the symbol [Symbol]; that is, three suns, an attempt to figure the refraction and dispersion of light by the crystal.[697] The _soui che_ stone of the Chinese which is said to quench thirst if it be placed in the mouth, is almost certainly rock-crystal, for the Chinese, in common with the ancient Greeks and Romans, believed this substance to be a transformation of water, a kind of fossil ice. A similar power was attributed by Pliny to one of the varieties of agate.[698] Labrets of quartz are used in Central Africa and we have a very interesting description by M. A. Lacroix regarding these ornaments as worn by the natives of a part of the French possessions. In the land of the Bandas the natives highly prize a piece of rock-crystal so shaped that it can be introduced into the lower lip. This usage is confined to the basins of the Ombella, the Kemo and the Tomi, affluents of the Oubanghi. The following description of the labrets was communicated to M. Lacroix by M. Lucien Fourneau, Administrator of the Colonies: These objects, called _baguérés_, consist of hyaline quartz, perfectly transparent; they are very regularly cut, and measure from four to seven cm. (two to three inches) in length. Some have the form of a very elongated and pointed cone, without any protuberances, the greatest diameter being about one cm. (about half an inch); the others, thinner and sharper, have at the base a rim destined to hold them in place; in all cases a pad of thread constituting a kind of permanent plug, assures and completes their stability. Some women wear as many as three of these singular ornaments, thrust, point downwards, into the same lip. The most regular quartz crystals are selected, and these are chipped off and roughly shaped by blows struck with a hard substance; the quartz is then set in a wooden handle, and the final shaping and polishing are accomplished by friction upon a round slab of quartzite or sandstone. These slabs show grooves along which the crystals have been rubbed. On an average the time required is four or five days of five hours. The completed ornament is valued at nine pounds of red wood worth about $1.20; sometimes one can be secured for three chickens, worth sixty cents.[699] Those who cannot afford quartz labrets substitute wood, glass, or pewter. M. Lacroix draws our attention to the fact that a study of the processes employed in shaping and polishing these pieces of quartz is of great importance for the elucidation of the methods in use during the Stone Age.[700] A nose-jewel from the New Hebrides consists of a crystal of hyaline quartz reduced to a cylindrical form, one extremity having been pointed, while the other retains the natural faces of the crystal. This was passed through the septum of the nose, and was most likely worn as an amulet.[701]