2¢ Washington Head
Imperforate Flat Plate

Watermark Check - This stamp also needs to be checked for single-line watermark.
You should also check the type; the flat plate, imperforate stamp can be either of two types, I or Ia. See also: Identification Guide for Types I and IA

Watermark Type Number Privately Perforated by the Following Companies/Types
single-line I 409 Brinkerhoff I, II, IIa, IIb; Farwell 4A, 4B, 4A5, 5A4;
Mailometer I, IV; Schermack III; USAV I, II, III
none I 482 Farwell 4B; Schermack III
none Ia 482A Schermack III only - This stamp MUST have Schermack III perforations

see also: Private Perforations - Vending and Affixing Machine Perforations

Since the value of a particular stamp is often determined by the design type, it is little wonder that there are many forgeries in which the more common design is altered to look like the more expensive type. The type I stamp, can be altered to look like a type Ia, by strengthening the Toga rope and button. The imperforate type Ia stamp is exceptionally rare and is found as a privately perforated Schermack coil only, never as the fully imperforate stamp. At this time, any imperforate type Ia stamp offered fully imperforate without the Schermack perforations is therefore an obvious fake. According to the Robert A. Siegel census, only 38 copies of this stamp are known.

Needless to say this stamp should never be bought or sold without certification. If you should run across a type Ia stamp while sifting through a bunch of Schermack coils, you should consider the stamp highly suspect. You must have this stamp certified before offering it for sale. If the certification comes back positive, you will have made one of the great finds in philately and be rewarded far beyond the cost of expertization.

Washington Franklin Identifier Tool