We're not just playing with hot glass at Niche HQ! When a piece is finished in our Hot Shop, it goes into a lehr, a temperature-controlled kiln for annealing glass objects. Rapid cooling of hot glass generates an uneven temperature distribution throughout the glass, which results in stress sufficient to cause cracking before the object has reached room temperature. To prevent this, glass objects are annealed by cooling gradually in the lehr from a temperature just below the solidification point of the glass. Anneal cooling rate depends on the thickness of the glass and size of the object. When it's done, the piece is ready to be cold-worked - the collective term for techniques used to alter and finish cold glass. Here's how we do it!