Unintended Consequences

I’ve had several opportunities to visit the Corning Glass Museum and have enjoyed and learned every time I visited. Of course the highlight of the tour is the walkthrough of the Steuben glass production line where you can see high quality, and very expensive, objects of art being hand blown and engraved. On one occasion I was startled to watch an engraver finishing up an elaborate bowl when he stopped, called a supervisor over to talk about the bowl. After a short discussion the boss took the bow, walked over to a barrel and smashed the piece. I later found out that the bowl was a special design and would have cost (in 1950’s dollars) over $10,000. But art overcame finances and they started over again because of a slight flaw in the glass.

Most people don’t think of Corning as being in the ranks of crime fighting companies, but when it sold its Pyrex brand of glass cookware to World Kitchen in 1999 the company accidentally made the manufacture of crack cocaine a poster child for the law of unintended consequences.

Ordinary glass shatters when it’s heated too quickly. If you pour something hot in a standard glass the inside expands faster than the outside and the resulting stress cracks the glass. Pyrex, which was made of borosilicate glass solved this problem by altering the atomic structure of the glass. Because of the boron the structure of the glass remains the same size regardless of the temperature. 

When World Kitchen took over the Pyrex brand, it started making more products out of pre-stressed soda-lime glass instead of borosilicate. With pre-stressed, or tempered, glass, the surface is under compression from forces inside the glass. It is stronger than borosilicate glass, but when it’s heated, it still expands as much as ordinary glass does. It doesn’t shatter immediately, because the expansion first acts only to release some of the built-in stress.

The lowlifes that cook crack cocaine found out the hard way that Pyrex shatters when they try to produce their product and now they have to make do with metal utensils (that rust and contaminate) or break into the local high school and steal the lab equipment. I don’t know if this has cut down on the manufacture of crack, but anything that makes it more difficult to produce is ok by me.