Used by Germany from the early 1870’s through WWI for domestic and import arms. This would include: 1891 Argentine, 1893-1894 rifles, Gew 88, Gew 1898, 1908 Brazilian, 1909 Argentine, etc. Usually takes 3-4 passes for a spectacular blue/black. This is a particularly fine-grained surface well-suited to fine sporting arms. It has a nice blue/grey hue.