I like to use ethanol to clean some grades of ice water and kief. I usually add 5-7 grams of this hash to 113 grams of Ghee and make a batch of cookies.
If you didn't properly purge the Hexane, you could smell/taste it (IMO). I would use HPLC grade Hexane, I believe it is easily purged.
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After vac and you have shatter put shatter in pyrex. Warm to 100F. Spread shatter in the pyrex. Heat until hash, when looking from bottom of pyrex, appears dry. You will see it as it changes from the outside to the middle.
I put mine in a pie plate in water sitting on three lid rings in a skillet of warm water. It is heated with a hot plate. The EtOH is heated 130-140F with a fan blowing across the plate. I block the wind from the hot plate. I think it takes an hour or two to evaporate the liquid down to mostly...
You don't need to add salt to raise the boiling point of water, use vegetable oil instead.
Here is a decarb chart (from Jump), you can compare that to the temps you achive in the crock pot. As your material ages, it partially decarbs.
I use between 4 and 6 grams of hash to 113 grams of Ghee (basically a stick of butter). I make 30-36 cookies with it. Yes they are strong. You do not need to decarb unless you won't be baking, smoking, etc. My wife & I will eat between 2-4 cookies/day each. If you search my posts, you may find...
Get a SubZero extractor with dry ice. The 1/2 lb. model's dry ice sleeve is wide enough for commerical dry ice pellets to fit in w/o having to break it up. Blast with butane from the freezer, and blast at -65F. There is no "pooling" of butane vapors, because there is no vapor.
With having only a quarter (I am assuming 1/4oz), I would grind it after it is dry, and add it to one stick butter (def. not more butter) in a small pot. I prefer to use a double boiler as to not get my material too hot. If you don't have a double boiler, you can MacGyver one. Heat it for 2-3...