I just purchased a 50 cent Justice fractional currency note that was "net" graded by PMG due to the presence of an "ink burn". On the back of the note behind Spinner's signature are two dark ink spots which have some of the paper missing at the centers. My questions: - What exactly is an "ink burn"? - What caused the holes at the center of the dark ink spots? - How much does this devalue the note? In this case the "net" grade is AU55. Thanks for any help.
I would guess that the ink used to sign the front of the note reacts over time with the paper and starts to eat away at it. I don't know how much it would devalue the note, my opinion is that the signature is part of making the note legal so it wouldn't drop it much.
These holes are from the acidic ink used for the signatures, over time eating through the paper. One one hand it probably tells you it's a real note, on the other hand it's got damage... Dave
I've seen plenty of older obsolete notes with that same ink burn on them as well. Unless it is a rare note, I try to find cleaner examples. Nice color on the back though.......
Much of the older ink was ferrous sulfate and tannin from gall nuts. As this ink, especially in higher humidity., breaks down the cellulose of the paper and produced the structural damage. Many handwritten diaries , manuscripts, etc. with such ink are being further damaged if not sealed in an inert gas or vacuum, or at least keeping with low moisture. But too low moisture will break down the paper also....... The ink can be neutralized by archivists, but color change and other secondary damage can occur. Just keep it in the PMG holder. Jim
Lets see if I can post a pic (first time here). This is a good example of ink burn, it ruined the note. A white background may have been better to show the burn.