Description
Beautiful and functional pen that writes very well with a high-quality ballpoint refill and a touchscreen/stylus section on the other end, suitable for touchscreen tablets or phones (iPhones, Android phones, etc.)
Crystal is a material consisting of glass containing a certain amount of lead(II) oxide. Clear lead crystal glass was first produced on an industrial scale in 1676 by the English glassmaker George Ravenscroft. In scientific terms, crystal glass is not a crystal because the molecules are not arranged in a regular structure. Glass consists of a mixture of silicon dioxide (the main component of quartz sand) and metal oxides. When heated, it melts into a thick substance that is easy to shape (blow) and hardens upon cooling, without the formation of a crystal structure: glass does not crystallize but forms an amorphous solid. According to a 1969 EU directive, crystalline glass is the general designation for glassware containing metal oxides, but within that designation there are several categories. Only the more luxurious varieties are required to contain lead: 24 percent for lead crystal and 30 percent for full lead crystal. For the lower categories of crystalline glass and sonorous glass, 10 percent metal is sufficient. It doesn't have to be lead; zinc oxide, barium oxide, or potassium oxide are also acceptable. If it contains more than 30 percent lead, it's high-lead crystal, such as Swarovski (approximately 32 percent lead). The higher the lead content, the higher the refractive index. A material with a high refractive index exhibits more brilliance and has a richer color spectrum. Glass with a high lead content is also used in the nuclear industry because the lead blocks X-rays and gamma rays better than regular glass.
