1869, 7kr Blue (50, Michel
39a). Two vertical pairs, tied by straightline "LANGENBURG/14 DEC 69"
datestamps on buff cover to Philadelphia, "FRANCO" and rate marks,
red Philadelphia backstamp, bottom stamp of the left pair with minor corner
crease and top right cover corner trivial nick, otherwise Very Fine, with
1984 Thoma certificate (Image) 
1869, 14kr Orange (52, Michel
41a). Exceptionally well-centered and with bright color, tied by
"STUTTGART 7/11" datestamp on 1869 folded letter to New York, red
"NEW YORK PAID ALL", black "FRANCO", Very Fine and scarce as a single
franking to the U.S., with 1994 Thoma certificate
(Image)
1873, 70kr Red Violet (53,
Michel 42a). Vertical pair, Positions 1 and 4 from a sheetlet of six
with sheet margin at top and nearly complete single-line dotted dividing
lines, intense color and good impression, each with bold "STUTTGART MAR 10"
framed cancellationEXTREMELY FINE. A WONDERFUL AND VERY RARE PAIR. MULTIPLES ARE SELDOM SEEN DUE TO THEIR HIGH FACE VALUE.
Signed at the bottom of each stamp by Georg Buhler and with his 1994 certificate and 1994 Thoma certificate. Michel catalog value 15,000 Euros. Scott Retail as two used singles. (Image)