Drew,
I'm glad that you posted the picture of these barrels. Of course, I knew that there would be no "orange lace", or any indication of the laminations. But, a picture is worth a thousand words.
When making damascus steel knife blades, the damascus pattern is not visible during the grinding and sanding before etching. It appears to be a mono steel. The pattern only becomes visible after etching.
There was a question in an old thread, about the barrel grinder's contribution to the creation of the damascus pattern. They had none. The damascus pattern was not visible to them, during their work.
