These envelopes are from the Potter Style Antiquarian Note Card Book. I saw these in a real live brick-and-mortar store (which I visit so rarely), and I'm so glad I did, because all the online descriptions of this set do not show you how lovely the envelopes are!
You can have a look at the lovely cards here: they are modeled after antique marbled book covers. Really great stuff, and they take fountain pen ink well, too.
I like that the envelopes have their own built-in decorative labels, so to speak, and on the bottom envelope in the photo above, I added my own home-made glitter bats. (I used this bat punch on pages of the letter, and I took the bat confetti by-products of said punch and sprayed them with glimmer mist glitter spray, then glued them to the envelope.)
