Pure gold does not oxidise, but on 14- or 18-carat gold nibs thin tarnish or ink-residue layers can form that are perceived as discolouration; these can be removed without problems by placing the nib for several hours in clear water and then wiping it with a cotton cloth, stubborn layers also with a silver-cleaning cloth. Vermeil nibs (gilded sterling silver) and gold-plated brass nibs of older construction tarnish more visibly; a missing silver hallmark indicates gold-plated brass, which can likewise be cleaned with a silver-cleaning cloth. Displaced or slightly bent nib tines (spreading) should not be corrected by laymen by pressing on paper, since this easily destroys the nib's tuning; for small misalignments going to a nibmeister or qualified specialist dealer is preferable.