An antique miner's oil lamp (often referred to as a "Betty" lamp or a lenticular miner's lamp). Lamps of this type were widely used in Europe and the United States during the 18th and 19th centuries, serving primarily to provide illumination in mines, tunnels, or underground spaces. Key features of the item include: a flattened, lenticular shape—the lamp's body is rounded and flat to stably hold the oil (typically whale oil, animal fat, or vegetable oil); and a long suspension handle—the lamp is equipped with a large metal arch and a handle featuring a hook at the end, designed to allow the miner to hang the lamp on a mine wall, on wooden beams, or directly on his helmet while working.