Glass tends to break easier than expected whether it’s due to a smash, crack, fall, or even a microfracture— it’s always tragic to see newer pieces gone too soon. How is it though that some water pipes can’t endure much wear and tear, yet others make it to see longer days? There are a couple key distinctions when it comes to the quality of glass. From the kind of material used down to the way it is made, form follows function. So what really defines a good quality glass piece? There are many crucial components that factor into the overall quality of pipes, beakers, bongs, and other glasswork, but first, you must understand the functional distinction between American blown glass and foreign manufactured glass. The process for American blown glass requires a dedicated artist to professionally torch and recreate a raw, glass-like tube material at a high temperature and turn it into a functional work of quality art. Large foreign production factories, however, have no demand for developing or improving glass pieces. They intently focus on the current market demand, rather than the quality of the glass. Some of the most distinct differences between high quality and low-quality glass are:
The best quality glass is typically hand blown (.doc) from a material called borosilicate, often referred to as boro. Boro is a toxin-free glass material that is resistant to breaking from temperature changes because it demands such an extreme temperature to condense or form its shape. In labor-based manufactures, oftentimes the glass making process uses cheap materials like soft glass instead of boro and mass production instead of hand-blown methods. This results in a vulnerable and sensitive product.
Kauzmann temperature is the liquid-glass transition referred to as the temperature where liquid entropies becomes less than that of the crystal. It sounds confusing, but it really just means that the temperature of the glass is at a point when it’s so hot that it becomes viscous and is ready to be molded. Because soft glass is more delicate than boro, it requires much less heat to obtain a Kauzmann temperature. This also means that the final product is just as delicate, though. The high temperature that boro demands to mold its shape ensures a hard, durable, temperature change resistant final product that you simply cannot get with soft glass.
Production factories tend to use the cold working technique, a process that uses power tools to change or form glass followed up with heat based condensing as a technique to relieve residual stress. Modifying the glass after it has been cooled can cause microcracks in the piece altering the quality of the final product. Hand blown glass techniques never attempt to modify the glass after it’s been cooled, which means you can say goodbye to microcracks!
Genuine glassblowers use an oven like chamber called a kiln to cool down their glass once the formation process is done. This chamber provides a warm, safe enclosure for the finalization as the glass pieces set into their final form. The kiln gradually brings down the temperature so that it is not drying out and cooling at room temperature, which can affect the way the glass will eventually react to temperature and shock. Kiln however are expensive pieces of equipment not often found in factories so instead they jeopardize the glass by cooling down at room temperature.