Recently I picked up this never-used Lyman round-ball mould that is unlike any other I've ever seen. It looks like brass but responds to a magnet. Tonight I took it apart and thoroughly cleaned it for safe storage. The picture below was taken after the cleaning, so the color is definitely not any type of residue and it's also the same color inside the threaded hole for the sprue plate screw.
A person who many consider to be an expert in bullet casting said that the Meehanite which Lyman uses can be a yellowish color after the machining process and before the bluing process. He wonders if perhaps someone forgot to put it through the bluing process before shipping it.
Your thoughts? I find it very interesting and unique.