Watermark Checking On Cover??

I was curious if there is a fairly accurate way to be able to check for watermarks on a stamp while still on a cover? I have bunches of 1 and 2 cent postcards from the washington/franklin era and a few outwardly checked items could be worth more on cover than as a loose used. again I know rarities are as such...rarities, but is there a UV way or good chemical or other way of checking for the watermark via the front of the stamp.

As far as I know there is no way to check for a watermark without lifting the stamp off the cover.

Peter

I've been able to do it on occasion using this technique, though it really depends on the strength of the watermark and the thickness of the paper/postcard.

Postmaster, thanks..that is a great thread/post. I'll eventually try it. I was also under the impression that one or the other of the two wavelenths of UV could possibly pick them out but I was sceptical about the claims.

I would advise you to not remove them from your postcards. If you do you will lose all the information that goes with it and you can't ever re-attach it.

Also, thinking about it a bit you can always use the date of the cancel to help ID your stamp(s). This site - http://1847usa.com/washfrankmain.htm and the date on the C.D.S. (Circular Date Stamp) will be of great help to pin them down. I hope this helps you out a bit? Cheers -Jeff