Due to the chemical make-up of HT9000, an amine blush may be seen after curing, which many people often mistake as uncured resin. To tell the difference between amine blush and uncured resin check the cure after a day or so with a fingernail. It should be difficult and/or impossible to dent. Amine blush can be removed with fresh water, or water with a drop of detergent added. Sand the surface, and then continue with the system.