Everyone knows that crystal is a sure sign of wealth and style. If you have class, you have crystal. It’s that simple. But what exactly is crystal? What makes it so valuable? How does it work? How is it any different from glass? These questions and others can make a person quite curious. If you want to know more about crystal, take a look at a few of the details to follow.
All crystal is glass, but not all glass is crystal. Standard glass, such as what you might find in a drinking cup or a window pane, is called “soda-lime glass,” because sodium carbonate and lime are two of its ingredients (along with dolomite, silicon dioxide, aluminum oxide, and several fining agents). There are two kinds of crystal: true crystal and lead-free crystal. True crystal is exactly like soda-lime glass with one particular exception: it has 30% lead oxide. (Lead-free crystal uses barium oxide.)
Why lead? Well, first of all, it lowers the temperature you need to work with the glass. When working with soda-lime glass, you need extremely high temperatures to mold and shape the glass into designs (usually about 2400 F or 1316 C), but crystal does not have to be kept in such heat when designers and manufacturers are working it. Lead crystal also produces molecules with a three-dimensional grid pattern, leading to a much higher refractive index than that of soda-lime glass. What’s “refractive index,” you say? It’s the quality of a material to change the direction of light. The high refractive index of crystal is what gives it that incredible sparkle and shine. Finally, crystal absorbs less kinetic energy than soda-lime glass, meaning that when it is struck (when vibration is applied), it oscillates (the vibration is sustained, instead of absorbed). This results in the telltale ring of crystal, often heard when beauty pageant contenders play champagne flutes or wine glasses.
In spite of the dangers of lead leaching, lead crystal is actually quite safe. The amount that seeps into consumables during the normal use and operation of lead crystal containers is well below hazardous levels. So don’t worry about that (although you probably shouldn’t let children too close to your crystal).
Crystal is an amazing thing. Now that you know a bit more about it, you are becoming well-educated in how to pick it out for your home. It is always a fantastic addition to any home.
