>iron of old chain and anchors of pre and WWII Japan contains slag which, it turns out is perfect for use by the blade, chisel, and plane masters. Sort of like finding a great tree, storing it and parceling it out for special work. I'm told that this metal is no longer available and as a result the prices were way, way, way above what one would expect to pay for scrap, "historical" anchors, or any relatively common metal item. The sale was public, but the bidders were agents, again I'm told, for very secretive folk. Two thousand years of skill, oneupmansship and trade secrets are hard to change. Not only did the anchor's metal content stay secret to most observers of the sale but so did the buyers who could use it for better tools.