Westmoreland glass was made by the Westmoreland Glass Company of Grapeville, Pennsylvania, from 1890 to 1984. They made clear and colored glass of many varieties, such as milk glass, pressed glass, and slag glass. It is unlikely that any American glass factory produced Mary Gregory-style glass before Westmoreland Glass Company's 1957 line. For more information, explore our identification guides for colored glass, pressed glass and its colors, Mary Gregory glass, carnival glass and its makers, and Depression glass and its patterns.