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