| Crystals, as we know them in their industrial | | | | crystal, it must be at least 10 % lead. The |
| applications were discovered in the 17th | | | | result is a heavier, clearer and more |
| century. They are traditionally hand blown. | | | | lustrous glass-like substance. It can be cut |
| Crystals are manufactured through the same | | | | to take many shapes and forms -- making it |
| process as that of glass forming; the only | | | | ideal for many applications, including |
| difference is that instead of soda ash, lead | | | | fashion accessories. |
| oxide is used. For glass to be considered | | | | |