A Babe Ruth autograph could sell anywhere between $4,000. to $20,000. and up. Depending on the Item signed, condition, and the type of authenticity that accompanies the signature. Even a "cut signature" The lowest price for a signed item (a signature on a piece of paper, or "cut" from a larger piece) will sell in the $2,000. range. As far as his last autograph being signed on his deathbed (I'm assume you mean before he died) you will have a hard time selling it as such without strong letters of provenance. Provenance is the ultimate proof of the origin or source from which something comes, and the history of subsequent owners. Provenance can come in different forms and with varying degrees of impact. In order for provenance to have an impact in authenticating an item like this it must come from a verifiable source. For example, a letter that comes from a source like a doctor that is know to have treated "The Babe," or a family member. Without this it is just merely an old $10,000. Baseball with Babe Ruth's signature on it. An autograph (baseball?) of such historic significance would be well known in the hobby, and would have already been sold for hundreds of thousands of dollars, if not in the hall of fame. I have never heard of such an autograph, and without Provenance it will not exist beyond a story told by the owner of the ball.
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