Instructions
Hold the item to the light and look for an apple-green color with a high degree of transparency. Opaque items with a significant tinge of yellow are more likely to be Vaseline glass, with which depression glass is frequently confused.
Examine the item to ascertain whether it is a piece of pressed rather than hand-blown glass. Machine-made by forcing molten glass into molds, depression glass should have an impressed mark on the base and a rounded rim.
Consider the function of the piece. Depression glass was generally made into utilitarian items such as pitchers, tea sets, jelly molds, dessert bowls and covered cake dishes. If a piece is primarily ornamental -- it's a figurine, for instance -- it isn't depression glass.
Run your fingers over the decoration. Because it was made in a mold, you should not feel any sharp corners, even on angular designs. Beading, ribbing and floral swirls are all commonly found on depression glass.