FREE Shipping on all USA orders!Lead crystal, (also called crystal), is lead glass that has been hand or machine cut with facets. Lead oxide added to the molten glass gives lead crystal a much higher index of refraction than normal glass, and consequently much greater "sparkle". The presence of lead also makes the glass softer and easier to cut. Crystal can consist of up to 33% lead, at which point it has the most sparkle. The higher lead content also makes it much more difficult to form crystal during blowing.
Englishman named George Ravenscroft discovered crystal in 1676 searching for a way to improve the luster and clarity of his glassware. He found that by adding lead oxide to his molten mixture he could not only improve the clarity (crystal clear) of the glass but dramatically increase the weight, the index of refraction and the ability to cut the material without fracturing. This new glass became known as lead crystal and very quickly became the perfect medium for glass cutters and engravers. Over the past 300 years, their skills, proudly passed from generation to generation, have given lead crystal it's world famous reputation.
The presence of lead in crystal softens the glass and makes it more accessible for cutting and engraving. Lead increases the weight of the glass and causes the glass to diffract light.. Lead crystal is made from a mixture of sand, potash (potassium carbonate) and lead oxide. The components are heated to at least 2,400 degrees Celsius until molten and red-orange in color. The temperature is then slowly reduced to the "working" temperature.Glass can contain up to 40% lead, if maximum hardness is desired. On the other hand, crystal can contain less than 24% lead if it has a high proportion of barium oxide, which ensures high quality light diffraction.
The main difference between glass and crystal is the lead content. Glass is composed of sodium and potassium. Crystal is also composed of sodium, but in addition, it contains silicone, and has a lead content of 10-24%. The lead makes the glass heavier and, most importantly, the lead changes the refraction index of the item, which makes it appear brighter and cleaner. Because the refraction index is higher and lead crystal is not as brittle as standard glass, it is possible to make deeper and more complicated cuts in crystal.
Makers of lead crystal objects include Baccarat in France, Royal Leerdam Crystal of the Netherlands, Steuben Glass in the United States, Waterford Crystal in Ireland, Mikasa in Japan, Swarovski in Austria, and Preciosa Crystal from the Czech Republic
