US 1925-55 Special Handling Stamps 10c 15c 20c - Wet Or Dry Printing?

Good Morning,

I don't have a good grasp on wet / dry printing - I have seen examples online and sometimes dry has a very white looking paper - but people have contradictions in their explanations so I've scanned the front / back to be certain.

Please have a look at let me know what you believe these are.

Also, I believe the 20c is a deep green based on the color differences in scrolls but again, not versed enough to tell.

10c Front / Back



15c Front / Back



20c Front / Back



Thanks for looking

As I recall, the best method for identifying wet vs. dry for the special handling stamps is to have both versions in hand & to compare the physical sizes of the stamps. The wet printings shrunk a bit in the horizontal direction, making the dry printed stamps about 0.5mm wider than their wet counterparts. Easy to see with the stamps in hand, not so easy to measure with a metric ruler. I also remember finding that color was not a very reliable indicator. If you belong to the USSS, you can search their "The United States Specialist" archives for an excellent article on the identification of these stamps. Will look for the title & author of this article later today. If I find it, I'll pass it on.
Added: Size Differences Between Wet and Dry Printings from Flat Plates - Wallace Cleland in the Nov. 2003 United States Specialist (USSS)
Found the above on the stampsmarter web site. This site also contains good info about distinguishing between wet & dry printed stamps. Search for "wet vs. dry".
Below is a size comparison for the 15-cent QE2. Wet at the top, Dry at the bottom. Note that shrinkage can actually take place vertically as well as horizontally, but since the stamp is wider the size difference is more noticeable in the horizontal direction. While there are color & gum differences, I've personally found a size comparison to be more useful.

My 2c worth...In 'wet' printing the paper is dampened before printing and the ink generally seeps out into the stamp more making edges seem a bit fuzzier when examined closely. In the Liberty Issue of the 1950's the stamps also appeared shinier when held at a sharp angle to light. Without one to compare side to side it can be difficult to see at times.

See this link
https://www.pnc3.com/primer/primer003.htm

The backside of the Liberties tend to be whiter and paper is slightly thicker.

Do these comments imply that wet and dry are two different varieties ?

They are listed that way in the Scott US Specialized catalog.

Thank you for that definitive example. It's very easy to tell the "wet at the top, dry at the bottom" differences!

One last observation. The use of design size as an identification tool for wet vs. dry printing generally works only for flat plate issues. This includes the QE (special handling) & J78 ($5 postage due) stamps. The Liberty series and the airmail stamps of the late 40s as well as postage due stamps after J78 are rotary press stamps ... there is no significant shrinkage for these, so other criteria must be used for distinguishing wet printed stamps from dry printed stamps. I would strongly recommend visiting the stampsmarter web site ... it contains a very good summary of how to id these stamps.

Yes they are and when they were printed is specifically known. To avoid double posting I direct your attention to this thread: https://goscf.com/t/74586 and the ninth post where I added extensive print history regarding the DRY PRINTED variety.

Edit: It has a piece of SH eye candy as well.