Additives are everything you embed or suspend in resin — glitters, foils, dried botanicals, clay slices, and charms. They're what turn a plain pour into a piece worth buying.

Let the resin thicken slightly before adding glitter, or pour in layers — a thin base coat, then the glitter layer once tacky. Our resin tips guide covers suspension tricks.

Most dry, stable items embed well; anything containing moisture (fresh flowers, food) must be fully dried or sealed first, or it can cloud and spoil in the casting. When in doubt, test one piece before a production run.