The amount of keif from bud is about 10-15%. Anymore and it's not pure, so you'd just have VERY fine weed. And the trichomes do not contain 100% THC. They contain whatever the genetics are capable of. If the plant is harvested, say at 27% THC each trichome [crystall] will contain 27% The crystalls are not the THC, they contain the THC/cbd cbn cbg blah blah blah.

So, you DIDNT get an ounce of keif from an ounce of herb.