Stamp Sheen

Can someone tell me what is the cause of a shinny glossy sheen on a stamp or maybe what is the term for it? I don't have the stamp(s) on hand to post a pic

We would need a photo to be better able to offer any opinion. Try to get a scan posted when you can. That way we can see the country of issue, time period and other facts about your stamp.

Don

The surface of a stamp - the front where the design is - may be shiny when the paper was coated [an extra layer applied to the surface] OR the surface was calandered [sort of brushing up your shoes without shoe polish!]. The coating not necessary shines by itself but in most cases it does!

Coated papers are called "chalky" in the stamp catalogues. To me that term is unfortunate because the sort of chalk that we once used on blackboards and children (and others) might still use to draw on sidewalk is not glossy but leaves a rough residue. Of course with proper application to paper, clays (isn't that what they actually use to prepare "coated" papers?) can create a very smooth coating that permits high quality photo printing.

After I realized that "chalky" means "coated" as in the coated paper used for high quality photos in magazine and book publishing the stamp catalogue term became clear to me.

I suppose "coated" would also be confusing to the neophyte. The first time I heard "coated paper" with reference to high quality photos in books, I didn't understand it either. I suppose "glossy" (which we do use, at least in the United States, to refer to coated papers), might have more widespread recognition. But a surface can be glossy for various reasons, which is why the OP asked the question in the first place.

The take-away from all this: technical terms in any business or hobby or popular culture area have specific meanings that have to be learned. Few terms, in and of themselves, are immediately understandable in their specific applications in sub-sectors of technology or culture. Some technologies, of course, become so common and taken-for-granted that the technical terms surrounding them become commonplace. But we don't always, at first glance, grasp how they transfer from one subfield to another. In this case the transfer is from macro-printing of books and magazines to microprinting on stamps. Common to both is PAPER.

So it's not a chemical breakdown of the ink. Does it make the stamp undesirable?

Perhaps it would help if you could describe which stamp you have a question about, country and catalog number.

When I get back in town I will post pic. Thank you everyone.