How are crystal glasses made?

Answer 1

ManufacturingCrystal is more commonly perceived as glass. The inclusion of 24 percent or more of lead oxide is what makes crystal what it is. The glass is composed of three ingredients. One is sand (silica). When the silica is heated to extreme intensities, the sand forms into a fragile state of glass. Soda ash (sodium carbonate) is a white, powdery material that is added to prevent the melting temperature of the sand. Last is limestone (calcium carbonate). This helps to make the glass firmer and stronger. When the lead oxide is introduced to the glass, it adds the brilliance and weight. The lead also makes the glass more malleable for cutting. The ProcessThe ingredients for the crystal are mixed and heated at temperatures that can reach 3,600 degrees Fahrenheit. The lead oxide will then be placed into the furnace. The amount of lead introduced enhances the beauty of the product. Most crystal items will not contain less than 30 percent lead. Glass WorkingWhile crystal is blown glass, it is necessary for four or more people to work with it due to its weight. The crystal begins as nothing more than a ball of molten glass. The workers are placed in groups around a furnace. They remove the ball from the furnace on an end of a blow-iron. Shaping and AnnealingA glass worker will blow through a tube to form a hollow sphere. This steel tube is 4 feet long and is continually rotated. Molds are used to create a shape. Once the molten glass touches the mold, it will begin to cool rapidly. The workers must move quickly to form the crystal. CuttingOnce the desired shape of the crystal has been achieved, it is taken to what is known as an annealing oven. The annealing oven is a long chamber where the crystal will go through variant temperatures. The process keeps the crystal from shattering, since it is necessary to prevent it from cooling to soon. The process can take as little as 2 or as long as 16 hours. PolishingOnce the annealing process is complete, the crystal is now ready to be cut. This is an important process. A pattern is drawn on the crystal, and the design is roughly etched. The crystal is then held against the edge of a cutting wheel to refine the design. There are two basic cuts: wedge cuts and flat cuts. Wedge cuts produce the deeper facets, and flat cuts create contrasting cuts.Once the crystal has been cut, it is placed into a mixture of hydrofluoric and sulfuric acid. The crystal is then rinsed, and transforms into a sparkling piece of art

Answer 2

Crystal glasses are made by heating a mixture of silica sand, lead oxide, and other minerals to high temperatures. This molten glass is then blown or pressed into molds to shape the glassware. The addition of lead oxide gives crystal its distinctive clarity and brilliance.

Answer 3

Making crystal glasses various from country to country. Lead is often added to liquid glass to allow it to be cut easier. A great video explaining the whole process can be found here http://www.YouTube.com/watch?v=6c_8ekySU3c.