What is Depression Glass?
Depression glass is clear or colored translucent glassware that was distributed free, or at low cost, in the United States and Canada around the time of the Great Depression. The Quaker Oats Company, and other food manufacturers and distributors, put a piece of glassware in boxes of food, as an incentive to purchase. Movie theaters and businesses would hand out a piece simply for coming in the door.
Most of this glassware was made in the central and mid-west United States, where access to raw materials and power made manufacturing inexpensive in the first half of the twentieth century. More than twenty manufacturers made more than 100 patterns, and entire dinner sets were made in some patterns. Common colors are clear (crystal), pink, pale blue, green, and amber. Less common colors include yellow (canary), ultra marine, jadeite (opaque pale green), delphite (opaque pale blue), cobalt blue, red (ruby & royal ruby), black, amethyst, monax, and white (milk glass).
Although of marginal quality, Depression glass has been highly collectible since the 1960s. Due to its popularity as a collectable, Depression glass is becoming more scarce on the open market. Rare pieces may sell for several hundred dollars. Some manufacturers continued to make popular patterns after World War II, or introduced similar patterns, which are also collectible. Popular and expensive patterns and pieces have been reproduced, and reproductions are still being made. source: Wikipedia