Originally posted by briank:
The autograph would be the same on a flat mounted sheet or on a loose sheet...at least back the newsprint with some type of non-acidic paper to stabalize it.
Newsprint is a problem. Deacidification is temporary, at best. When the discoloratrion happens years later, it may be blotchy. That is, darker in some areas and lighter in other areas, depending on the density of paper fibers and their absorption of the buffer.
I disagree that the autograph would have the same value regardless of the substrate. I once framed a George Washington signature, which came on a small, irregularly-cut piece of paper. The customer said it was originally on an envelope, but a previous owner had trimmed away the rest of the paper, believing that only the signature had value. He told me that several appraisers informed him that if the envelope had been left intact, that it would be worth thlousands of dollars more.
I agree that the newsprint will deteriorate, and that proper mounting would prolong the useful life of the sheet by giving it a stable substrate. But if it is to be done, a conservator should do it. I would not. I doubt that the value would be enhanced by mounting, and it could be reduced.
The larger question is: How far should we take the "mounted is better" idea? If it's OK for newsprint, then what about art on fine paper? What about a wadded-up or torn concert poster, signed by a celebrity?
Maryann's words are my words, and still true of any collectible thing. Anything that changes the condition reduces the value.