Unidenified Stamp - Need Help Idenifying A Stamp

I have tried all the normal routes to ID this stamp but have little to go on, except that a coin, the Colombia Half Dollar, was also minted at this time for the same celebration.

United States Constitution Sesqci-Centennial Commission For South Carolina
Created by Resolution Of The S.C. General Assembly
May 23rd 1788 - Three Bust - May 23rd 1938

There is no denomination on the stamp. I am going to try to upload a photo of the stamp.
Any help would be greatly appreciated.

Several stamps come to mind, but none perfectly match your description. All three have the denomination clearly shown. All were issued in 1938.

Scott 835 is a 3c deep violet stamp commemorating the 150th anniversary of the ratification of the US Constitution.

Scott 836 is a 3c red violet stamp commemorating the Swedish-Finnish Tercentenary landing.

Scott 837 is a 3c red violet stamp commemorating the Northwest Territory Sesquicentennial. The last one depicts three standing individuals.

Once you upload, we can match it.

If there is no denomination on the stamp, then it is not a "postage stamp" but likely a commemorative "poster stamp" or "cinderella" as they are commonly called.

Once again, we'll need to see a scan of the image to properly identify it.

Very nice Cinderella.

How do you find the value in an item like this. I am just now getting my collection ready for sale, and am finding out how much I don't know about stamps.

something like that local stamp is worth a dollar or so. You need to find a collector who has a interest in that field.

Thanks for all the help, I am glad I found this site. Lot of info and informed posters. I think my next step will be to contact some S.C. stamp clubs and see if I can hook up with an interested party. Maybe someone has the coin and needs the stamp to complete the collection.