Thanks Brian for the help

Thanks Brian for the help

Brian do you have contact infomation for Stan Challis? It is a good idea to contact Stan.
Larry

Brian Thank You for the input, I will try to buy a copy of "Irish Diamonds" book. The publisher says it is sold out. Not listed in any of my searchs today. Is it possible to get a scan of the page that mentions this postmark. I will try to figure out a method to sort my 250,000 four corner...

Thanks, my original post is not clear, i know it is Dublin. What does the small 6 in the triagle stand for.

Need identification on four corner penny red postmark. Ireland 186 with a 6 in the triangle.
Thanks Larry

Thank You that is correct Penny Reds with letters in all four corners. This program will help to Identify the unreadable plate number.

I am almost finished with a database with all 144,960 cropped corners of the four corner penny reds. If I produce a free program for you to visually compare your unidentified Penny Reds to these cropped corners to determine the plate number, will collectors use or want such a program? I am still mis...

What full sheets of Four Corner Penny Reds are known?