At Crystal Delights we talk a lot about the differences between high quality American made glass products and the way less-expensive, imported alternatives. But it’s one thing to say there’s a difference, and another thing to see the difference with your own eyes.

Crystal Delights lampworker at the torch

Crystal Delights lampworker at the torch

We recently used our polariscope to compare our glass to some of our foreign competitors. The polariscope works by transmitting polarized light into the glass; any modification to that light due to features of the glass can be seen by the viewer. If the glass is stressed, you will see brown coloration or rainbows, and it is most likely because the glass was not properly annealed or annealed at all. A good, strong piece of glass with no stress should look crystal clear.

When we put the glass products we believe are made in Asia under the polariscope, they are quickly revealed to be a poor quality, stressed glass. As you can see, it has both brown coloration and rainbows, both signs of stressed glass. This would be an indication that the glass was not correctly annealed.

Then we tested one of our plugs, and as you can see, the difference is clear…crystal clear! This is how a high quality, properly annealed piece of glass should look; no rainbows or discoloration, just perfectly clear glass.

A non-Crystal Delights product under the Polariscrope showing stress

A non-Crystal Delights product under the Polariscrope showing stress

A Crystal Delights product under the Polariscrope showing no stress

A Crystal Delights product under the Polariscrope showing no stress

Another non-Crystal Delights product under the Polariscrope showing stress

Another non-Crystal Delights product under the Polariscrope showing stress

 

We achieve this by properly annealing all of our glass pieces. This process involves heating the glass until it reaches its “stress-relief point,” which is over 1050 degrees. It is then held at that temperature for a specified time

according to the piece’s design until the temperature is even throughout. The glass is then slowly cooled at a specific rate until it reaches the “strain point.” This process, performed by our skilled professionals, relieves the glass of any internal stresses that resulted during the forming process, and brings the glass to its absolute strongest state. This is what makes our glass extremely safe, durable and yes, more expensive.

A Polariscope for testing stress in glass

A Polariscope for testing stress in glass

Mass produced glass products most likely have NOT gone through this process, as it takes time, skill, and resources. The manufacturers of these products are more concerned with their bottom line than they are about making sure their products are safe and long-lasting. The result is a product that is not only inferior, but could potentially be dangerous too. Glass that hasn’t been annealed is more liable to crack or break.

Now that you’ve seen it with your own eyes, can you believe the difference?!