1851-57 12c Washington

It's the block of eight shown above, but I couldn't find it anywhere, including the early certificates. I know that the PF has books with all the issued certificates pictured; I thought that the early certificate images had all been put up online. Not sure why this one is not included.

I could not find the cert either. Too bad the block of 8 was broken up into two blocks of 4.

I am sure that was done to sell them; it's much easier to sell a block of four than a block of eight. Unfortunately.

Here is a general rule to tell if this stamp is a plate 1 or plate 3 if the guide dot is visible.
If the guide dot is on the top right then it is plate 1.
If the guide dot is on the bottom right, follow this rule:
All of plate 1 LR guide dots are to the left of the inner right frame line.
All of plate 3 LR guide dots are to the right of the inner right frame line.

Here is a link to the work done on the 12c issue by James Allen. It took me a while to find it and I thought it should be posted here for others to look at. Without the work done by Mr. Allen, I would not have had anything to work on for plate 3 left pane. I think that I have found most of the stamps he used for his plating efforts in Siegel auctions. But there were 3 groups that were lumped together without images. I have plated every block I found on Siegel except 2. Those two blocks are from plate 3 left pane but have no overlapping positions to locate their place.I am still hoping to find some block to connect the pieces of the left plate. Plate 3 starts on frame 7. Here is the link to Mr. Allen's work:
https://www.uspcs.org/resource-cent...f-1851-1861/

here is a nice single and pair on cover.

Nice cover.
The Philadelphia British packet is nice and less common than NY or Boston.

Thank you TX, yes the Philadelphia PKT are not common. I love all the position of these 36B
I think the page came out great.

There are two double transfer stamps on the right pane, 28R3 and 98R3. That page has both of them. Position 97R3 is the only right pane position missing the left outer frame line. So all three stamps are special.

Here is a nice one that I just got.
It is position 20L1, Scott #36.
Not many centerline position were perforated between the panes.
I would like to reconstruct plate 1 of the 12c.
Only 99 more for the left pane.

Here are a couple of pairs from the right pane, I believe both are 21-22R1, one perforated, the other not. Any thoughts on why some centerlines were perforated and some not? Are there enough found on cover or date stamped to know if it was a consistent change made over time, or was it by random chance (human error) that some got perforated?


And here is a perforated centerline that I have from the left pane, I do not know the position.

Zebraman - both pairs are 21-22R1 like you said.
The single is 40L1 (see image).
Notice the marks in the right selvage.