1c-$5.00 Columbian, Plate
Proof on Card (230P4-245P4). All have large margins and rich color, a
Very Fine set (Image)
3c Columbian (232). Mint
N.H., well-centered, rich color and proof-like impression, Extremely Fine
Gem (Image) 
4c Columbian (233). Mint
N.H., perfectly centered with wide margins all around, deep rich color,
light natural gum skip at top and trivial natural inclusion in margin
(neither mentioned on accompanying certificate), Extremely Fine and choice,
a beautiful stamp, with 2000 P.F. certificate
(Image)
4c Columbian (233). Mint
N.H. left margin block of four with part imprint, gorgeous deep color,
fresh and Fine block, Scott Retail as four Mint N.H. singles (Image) 
4c Columbian, Error of Color
(233a). Mint N.H., beautiful deep rich color on brilliant paper, the
more intense of the two error shades, proof-like impression, centered low
with three wide marginsFINE. AN EXTREMELY RARE MINT NEVER-HINGED EXAMPLE OF THE 4-CENT COLUMBIAN ERROR OF COLOR -- AS FRESH AS THE DAY IT WAS PURCHASED AT THE POST OFFICE.
The 4c Columbian color error was caused by the use of a wrong batch of ink. Spectrographic analysis confirms that the ink of the 4c error matches that used for the 1c stamp.
With 1970 P.F. certificate (Image)