Consists of a scheme $X$, satisfying the following properties:

$X$ normal, integral, all stalks of the structure sheaf are domains, affine, reduced, excellent, pure dimension 2, finite dimensional, quasi-compact, locally noetherian, irreducible, all stalks of the structure sheaf are irreducible, noetherian, separated, dimension 2, connected, not regular

By the theorems, we also have {"X": {"quasi-separated": true}}