Using a black light for card diagnostics

If it is true that substances which contain brighteners will cause UV light to fluoresce, how can one determine whether a suspect corner was rebuilt, or accidentally smeared with a dollop of mayonaisse, and then wiped "clean"?

Gil, if you go in to the section of Useful Information, there is an article in there from Kevin about how to detect rebuilt corners and the use of a black light.

Jay

After reading that explanation, Jay, my impression was that you can not differentiate between brightners attributable to the adhesive used for rebuilt corners and those present due to other sources; by a black light assessment. If this is so, then a card doctor can hide the evidence of a rebuilt corner by immersing the card briefly in the foam from laundry detergent, for example.

But I am not certain of this, hence the inquiry.

The use of a backlight is typically done to validate an alteration(s) already detected. It is not only used for adhesives but also for chemicals, recolor (paint, ink) and some other advanced work.

To cover up an alteration is what make the difference between a basic card doctor and a pro. The more one can disguise or make a card look absolutely normal the better, but that requires skill. IMO 99% of the card doctors simply do a single alteration and see who they can get it past.

As in the example of the T206 Shappe error card that I showed on a previous post, that required at least five different alterations to complete cover work.

So, I guess to answer your questions Gil; the ultimate goal is to hide the evidence...just so few know how to do it. Rebuilt corners not only use a considerable amount of adhesive but also raw stock that becomes part of the card itself, not just a residue. That is tough to hide.

Hope this makes sense. Thanks for the opportunity to help and comment.

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