Oorijzer, Dutch for "ear iron". Originally a type of iron head-dress worn as peasant jewelry by the women of Friesland, in northern Netherlands, but later adapted as a gold helmet fitting tightly overthe head and worn under a lace cap. It has a cleft opening extending from the brow to the crown, derived from the 17th-century iron type, and is made with rosettes at the side that hide pins whichsecure it at the temples to the lace cap.