Old US Cover With Double Stamped Indicium One Part Albino

I recently came across a stamped cover with a partial and full indicium, the partial is Albino. I need help to ID the indicium as to when it was printed and the Scott #. It appears to be a U1 -10 which would make it one of the first embossed postage envelopes used. Can you help me to ID this from the photographs that I have attached?

#U9, die 5, white paper. Nice!

Its a double impression, with one albino.

If we can determine the knife and watermark, there's a chance it will get a catalog listing the next time the UPSS's 19th Century U.S. Envelope catalog is updated.

The watermark should be easy. All U9's are watermark 1, except one listing that is for unwatermarked paper.

There are three different knives for the U9's. The shape of the bottom flap is a useful discriminator. Could you do a scan/photo of the back side?

I took images of the back and noticed that the envelope was partially torn at the indicium. But here are the images.

Thanks Thomas, how can I get this listing in the new catalog?

sharons25,

Could you please provide a scan/photo of the whole front. Also, tell us the size (length and width) of this envelope.

Thanks,

Thomas

The envelope size is 5 1/2 x 3 1/4 in.

sharons25,

Thank you. Your envelope is a UPSS number 15-1.

I have added the scans documenting this double impression to the list of proposed additions to the Catalog of the 19th Century Stamped Envelopes ... of the United States for its next update.

I encourage anyone who is interested in postal stationery to visit our website (upss.org).

Thomas

Thank you so much!

Sharons25