Older chisels - color of metal

I was going through my chisel drawer yesterday, adding some new inventory and oiling them down, and I realized that one of my sets has a distinctly different color of metal than the rest.

Most of the chisels have the typical shiny steel shanks and surfaces, but this set, an older crank neck Buck Brothers (Bros) set of gouges, has what I would call "grey" steel. They are a very dull, light grey color. They have not been sandblasted, but they are the color that well sandblasted steel would be.

Does this strike a chord with anyone? Why would the color be so different on this set? Is this a characteristic of the type of steel, or a finishing processes done to the steel?

Thanks, Todd

All around, or just on one side of the bevel? Some bitted chisels might be different colors if it's only tool-steel on cutting edge.

What it actually sounds like is the color of some of the chisels I have that have been through a chemical rust removal process. The places I've polished them back up on the bevel and blade backs look normal.

All around (top, bottom, edges). The cutting edge, where they are ground and polished, is the typical polished steep, and I suppose if I rubbed enough and hard enough with abrasive I could remove it, but whatever it is, it's on there thoroughly, all the way up where the tang goes into the handle.

And, unless this grey stuff also operates like a metal filler, there are no visible pits where even light surface would have been. The metal is just as smooth as smooth can be.

A lot of people have used gun blueing or other chemicals on their metal tools to help prevent rust. Yours may have undergone this kind of treatment.

Also, if they were used by a person in a production shop, it might have been how they made their tools distinctive from other workers tools.

jtk

Some of my older chisels are like that. I have no idea why; I just figured it was patina and let it go at that.