The Scott Specialized Catalog of US Stamps & Covers lists 12 cancel colors on number 11A; blue, red, orange red, orange, brown, magenta, ultramarine, green, violet, purple, olive, and yellow; and a smaller subset on numbers 10, 10A, and 11.
Some of these colors are controversial, such as olive and green. A recent check on
ebay shows three ads for olive cancels on this issue, but all are black cancels with too much oil in the cancel ink. Too much oil in black cancel ink is notorious for resulting in a greenish or olive appearance.
Does anyone have any of the scarcer 1851-57 3-Cent imperforate cancel colors they can show?
Below is an image showing green cancels at left and right, and what I believe is an olive cancel in the middle, on #11A.
Regarding green and olive cancels, does anyone know of a reference listing which towns are known to have used these colors? I believe the town on my center stamp is Lancaster PA, and on my right stamp is York PA. I'm not sure about the town on the left stamp. Going on a Pennsylvania hunch, Boswell would be the best fit for the left stamp.
