McCoy pottery is widely collected, and many fake McCoys are being sold on the Internet. Luckily, there are several red flags and warning signs that scrupulous buyers can look for to ensure the piece is authentic.
Look for heavy fake crazing; crazing looks like a network of fine cracks in glaze. Sellers of fake McCoys attempt to pass off fake crazing as a sign of aging, but it is too dark, completely covering the piece of pottery, and far too even to be authentic proof of age. Be wary of pieces that have no history. Pottery that has been found at an estate sale or randomly discovered in an attic should be regarded with suspicion. On the bottom of items such as mugs, mixing bowls and flowerpots, authentic McCoy pottery has a circle with a tulip in the center. Within the tulip shape, there is a number that corresponds to how much the piece can hold. On the bottom of all pieces made after 1939, a stylized "McCoy" is written. All later pieces have the words "Oven Proof" in capital letters above the "McCoy" signature. Be sensitive to size because fake McCoy pieces can be shorter or more lightweight than an authentic McCoy would be.