Certificates of Authenticity (continued)
The Certificate of Authenticity should also include information that may or may not be specific to the artist's technique. For example, a Charles Fazzino limited edition might consist of a total of 265 pieces (edition size). Within that edition, there will be sub-editions, the total number of which should add up to 265. Each sub-edition is based on the same overall image, but will have a slight variation to it. The Certificate of Authenticity should describe the subtleties of each sub-edition.

Marked Up Charles Fazzino Certificate (Click to Enlarge)
Certificate in Detail
The Certificate of Authenticity illustrated above is an actual Certificate from the Charles Fazzino limited edition artwork titled "Just a Cab Ride Crosstown." From it, we can see that the edition was created and released by Museum Editions, Ltd in 2008. It is a hand-printed silkscreen serigraph printed on 100% museum board and the total number of pieces printed is specified at a maximum of 485.
Within the 485, there are four different sub-editions: Premiere (PR), Deluxe (DX), Trial Proof (TP), and Artist Edition (AE). The differences between them are outlined on the certificate. As you can see, in this case, the differences have to do with the number of layers to the artwork, the color of the board, and the level of embellishment. Sometimes the differences will include color changes between sub-editions or image size differentiation.
This Certificate should accompany piece #12DX from the Charles Fazzino limited edition "Just a Cab Ride Crosstown." In order to match up the Certificate with the artwork, the artwork should have number in the lower left hand corner that looks like this: 12/300DX (the 12th piece in a 300 piece deluxe limited edition).
Art Appraisal
A Certificate of Authenticity should never be mistaken for an Certified Appraisal. An artwork can only be truly appraised by a licensed appraiser and any accurate appraisal will take into consideration and artwork's history and condition, neither of which can be adequately evaluated unless the artwork is tracked through its entire lifespan.
The Point
Any gallery from which you purchase a piece of fine art should include a Certificate of Authenticity from the artist or publisher with your work. If it is not automatically included, ask for one! It will insure that you receive exactly what you think you bought!