Identifying R152 Varieties

I am looking for some assistance in identifying the variety of these two R152 stamps. I've looked through the Scott Catalog, and done some google searches but can't with much confidence identify which varieties they are.

Appreciate any assistance / opinions / links to sites that might help me figure these out.

Thanks in advance



*** Moved by Staff to a more appropriate forum. ***

When you say varieties, I assume you mean R152a, R152b, and R152c, and not the numerous plate varieties on each. For the latter, there are several threads here on the forum, as well as articles in The American Revenuer.

R152a, your left stamp shown, has blue silk threads visible.

R152b, your right stamp shown, has no silk threads, and is therefore the watermarked paper.

R152c, not shown, is rouletted rather than perforated.

This is an example of R152c:

Thank you! That is exactly what I was looking for.

Appreciate sharing this great info!

Have a great day!