What is the characteristic difference between crystal and glass? The distinguishing difference from crystal and ordinary glass is the powdery red lead oxide. The brilliant clarity and sparkle of Waterford crystal is obtained through its high lead content which is approximately 33 percent. Other ingredients include ultra-white silica sand, which makes up almost half of the mixture, potash and a small amount of recoloring agents. These elements are mixed together and topped by bits of broken crystal (cullet) taken from earlier rejects. When fired, the cullet melts quickly, helping the raw materials fuse into a molten mass.
Thick-walled ceramics pots, approximately 4' high and 3' in diameter, sit on ledges inside the firebrick furnace and are gradually heated from underneath by oil flame. Clay is used because it withstands high heat and imparts no color to the glass. The pots last about two weeks before being replaced.
The temperature inside the furnaces is brought to 1,2000 degree C. In about 36 hours the ingredients reach the proper state of melting. A higher heat is used for stemware because of the flexibility required in forming, while the arm of a chandelier needs lower heat because its long, thin shape must cool quickly and set to avoid distortion.
Waterford artisans are extremely skilled at diamond cutting. The brilliant stem wear and most bowls begin as spheres. They must be cut to create surfaces at the top. This is referred to as "cracking off the cap". An industrial diamond is used to incise the cap but not cut it off entirely. The incised piece is then rotated in front of a flame which separates the cap from the rest of the piece. For thin rims, a diamond cannot be used to cut all the way through because it would cause chipping.
Bowls, vases, salad bowls have to be 3/8" in order to apply the diamond tip saw and is used to remove the cap and then the pieces are ground and polished to a uniform smoothness.
With stemware, a tungsten-carbide belt is used to smooth the rim and bevel the edges. The rims then go under a glass flame which melts away any sharpness. This is called glazing. Each piece is then re annealed, as before, for uniform strength. The uncut crystal piece, called a blank, is now ready for cutting.
All of Waterford Crystal is cut,. The cutting is done entirely by hand. Along with clarity and sparkle, cutting is a distinctive hallmark of Waterford Crystal. Cutting patterns today are frequently based upon the original designs created during the 18th and 19th centuries. Waterford is the largest hand-cut crystal company in the world.
There are two types of cutting: wedge and flat. Wedge cutting is used for all of the intricate work. Deep wedge cutting creates prisms which diffuse light and intensity its reflection. Flat cutting is broad and without detail but very slow and costly. It is an alternative to intricate wedge cutting that works in combination to offer contrast. Flat cutting also can reach areas of a piece which are otherwise inaccessible to the wedge cut.
Prior to cutting, the blanks are marked with felt-tip pens as a rough guide for the designs. But it is the cutter's own sight and feel which are the true guides to position and depth. Cutters work in teams along a bench of wheels. The master cutter is at one end, followed by a qualified cutter and one or two apprentices. The wheels vary in diameter from 2 to 4 inches, depending upon the piece being cut.
One can easily see that the manufacturing and creation of fine crystal can be very expensive and time consuming. It is a labor of love for these Irish artisans who's pride, talent and dedication in delivering the finest crystal to the world market has made the name of Waterford Crystal synonymous with excellence since the 18th century. The next time you go to purchase a lovely Waterford Music Box or select a set of fine crystal stemware for a wedding gift the price will be reasonable for the treasure you've purchased.
Research data "Waterford" an Irish Art, 1981
http://www.melange-art.com
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