The problem with plain undyed bone is that it yellows with age like this example Jack posted. For some, this is a good thing, but to me it is not desirable. I realize this is just a matter of personal preference. If we go with smooth bone, undyed plain will probably win out, and we will end up with a knife that will eventually look like the one pictured below. I have owned plain undyed bone knives that turned yellow very quickly. Steel pins and liners might prevent verdigris, but they will not prevent the yellowing.
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