http://medithrive.com/concentrates1.html
http://en.wikipedia.org/wiki/Hash_oil
http://www.cannabissearch.com/concentrates/hash-oil/
Well-made hash oil is very high in THC, anywhere from
30 to 80% in fact. Consider that marijuana ranges from 5 to 35% THC, but most high-grade weed today is around 20% THC. Solid hashish ranges from 20 to 60% THC.