A rare pair of purple CD 131.4's. The left is embossed with the DEC. 19, 1871 Hemingray patent date, and the right is unembossed. It is not clear if the latter is a Hemingray product. Both are "only one known".

You can see the wear on the mold on the one on the left. Chunks of the mold are missing, creating irregular raised blobs on the upper wire ridge and in the wire groove.

The left one appears much taller than the right one, because of the nearly 3/8" base overpour .