Wergera "siderography" bo Zimanê kurdî

A 19th-century process of reproducing steel-engraved designs for printing: particularly, the transfer process invented by Jacob Perkins (1766 – 1849). The design is engraved on a steel block, then hardened and used to transfer a raised-image version to a steel roller under heavy pressure. The roller is then hardened and used as a die to impress duplicate images on printing plates for transferring to paper by the intaglio method as a 'siderograph'. [..]