Apple Blossom, which refers to the etching on the glass, was made by the Cambridge Glass Company in the 1930's.  It was made in amethyst, crystal, green, gold krystol (a lovely shade of yellow), heatherbloom (a very pale lavender), peach blo (a peachy pink), royal blue and willow blue.  It came in a complete line with bowls, plates, cups & saucers, candlesticks, pitchers, stemware, tumblers, platters, salts & peppers, vases, etc.  The crystal, yellow, amber, pink and green are found most often.   Pieces found in blue carry a premium as they are desirable and hard to find.