This model is rather big. You can find a smaller one, more suitable for earrings, keychains or pendants here: http://shpws.me/qGYr
Comes WITHOUT the chain.
Tetrahydrocannabinol (THC) is the main psychoactive substance found in the cannabis plant. It was first isolated in 1964. In pure form, it is a glassy solid when cold, and becomes viscous and sticky if warmed. An aromatic terpenoid, THC has a very low solubility in water, but good solubility in most organic solvents. (from Wikipedia)