Counterfeit card
A counterfeit card is a fake made to pass as a real one. A fake slab is a case made to pass as a grading company's. Both are checked against the real thing.
In more detail
Fakes exist in every part of the hobby, from sports cards to trading cards, and a seller or a marketplace will meet some. TCGplayer says on its seller blog that none of the techniques it describes are conclusive on their own: some fakes pass one test, and some real cards have printing quirks that look suspicious.
Cardmarket's guide shows the kinds of checks that catch many fakes: a missing accent in a printed name, a symbol that is off-center, an unusual border, a weak foil effect, a different font, text that does not fit the card, or a color that is much duller than a genuine copy. Compare the card with one you know is real.
For a graded card, look up the cert number on the grading company's site and compare the record and photo with the card, as the cert number entry explains. A real cert number does not prove the card in the case is the one that was graded, so check the card too.
Related terms
Where Rip.fan covers it
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