Look at the piece's shape. Authentic Pueblo pottery is handmade as opposed to being thrown on a wheel, therefore it is unlikely that it will be exactly even.
Examine the finish. Authentic Pueblo pottery is uniquely made in coils with old ground pottery shards. The coils are smoothed out and polished upon completion, and then a slip (either a clay or fine sand mixture) is applied, followed by more polishing, then painting and firing. You should be able to feel the coils on the inside of the pot.
Check the bottom of the piece. Authentic finished pieces must be labeled by their maker, according to the Indian Arts and Crafts Act of 1990.
Look at the patterns and designs featured on the piece. Typical designs on Pueblo pots include angular geometric patterns, floral, bird and animal patterns. Color patterns include black on black, black on cream and polychromatic.
Purchase pottery directly from the artist or through authentic Pueblo art websites. Notice when browsing such sites that there is only one of each kind of pot, indicating that they are handmade. Avoid websites or shops that sell more than one of the same pot, which means they are machine-made. Check the events requirements on Pueblo pottery items being offered for sale at annual fairs and other events to ensure the items are authentic. If you cannot find such requirements, it is likely the items for sale are not authentic.