Slag Glass Lamps

Slag glass (also called marble glass or brown malachite) is an opaque pressed glass streaked with milky stripes, usually white or off-white. A variety of objects were made of slag glass, and multiple lamp companies used it as a shade material. It’s often reverse painted with a scene or stained with a color. Slag glass production boomed beginning in England in the late 1880s, a trend that hit America not long afterward.