Last Updated: December 1996
This section on blade coatings was written by A.G. Russell, for the benefit of all of us here. This and similar pages can now (or sometime soon) be found on his homepage, http://agrussell.com/
Plating or Coating Blades
Blades have been coated in one form or another at least from the middle ages. The earliest I know of is rust bluing that would have been used to help reduce rusting and also for beauty especially where gold or silver was inlaid into the blade.
An early replacement for bluing is the Parkerized finish developed for the protection of stocks of rolled steel stored in the open, it began to be used early in this century as less expensive and more suitable to rough military finishes than bluing. This was as true of bayonets and combat knives as it was of guns. The only real excuse for use of that coating today would be to kill reflection. It is not a good coating for cutting as anything you cut will stick and not slide across the finish.
As soon as the electro-plating process was developed, people began plating knife blades with gold, silver, chrome, and probably as many other elements as they could think of both-to keep them from rusting and for beauty.
While stainless steel was developed about 1910, there was no useful high-carbon stainless available to the knife industry until the 1960s so some makers used plating, like Gerber's hard chrome, to keep rust down.
The problem was that the sharpened edge rusted and most people would rather have a knife that did not hold an edge like the high-speed Gerber blades but did not rust. So Gerber went to less expensive stainless and the customers were happy and Gerber made lots more money. If you can find the old high-speed steel kitchen knives put them to work in your kitchen, they will have rusty edges, so what?.
Some time in the 1930s or 40s, Robeson Cutlery offered hunting knives with tungsten carbide coated on one side of the blade. The idea was tha