Small, mushroom-shaped tools made of glass, designed to be operated manually like an iron to smooth, polish, and press linen materials, most notably starched collars and cuffs. As the precursor to metal irons, this tool did not require heat for use; instead, it was used cold and its rounded edges were rubbed over damp fabrics before and after they were washed to achieve the intendend smoothing and polishing effects. The tools were often used together with small ironing boards made of whalebone or other organic materials. Uitilized as early as the Viking period, these tools were equipped with handles in the 16th century to facilitate use. They were produced and used well into the 19th century before being replaced by flat irons.
