2 gram colour changing silica gel bag (orange to green).Silica gel is a granular, porous form of silica made synthetically from sodium silicate. Despite the name, silica gel is a solid. It is a popular desiccant used in many industries world wide. These Silica Gel beads are colour changing and will go green whilst adsorbing moisture. The bags they are in are small plastic zip-lock bags and unlike the sachets they are not porous, so the beads need to be taken out and put in the bottom of other containers from which to retain the moisture. It is recommended by experts that the equal weights of silica gel and seeds are used. This means one bag will help preserve around 50 cannabis seeds. Once used and green they can be slowly dried in an oven on a low temperature.