etchall Dip 'n Etch (32 oz) Re-usable! Use on: glass, mirror, ceramic, porcelain, marble, or slate. The Art and Craft Material Institute has approved etchall dip n etch to be used by children 12 years and older, children under 12 years can use etchall under the supervision of their parents. It conforms to ASTM-D4238. NOTE: The summer heat causes the product turn a darker caramel color than the usual white. The color of the product does not affect usability or performance; dark etchall is still good etchall!