I am a medical user who dilutes extracts and uses them sublingually. I bought a Coldfinger to make an extract. My question is: does marijuana have to be heated to become psychoactive?
My solution was to put the marijuana in the oven before putting it in the Coldfinger. I have no idea how long I should leave it in the oven or at what temperature. THC boils at 392 degrees. Do other cannabinoids which are essential to the experience boil off much more quickly? At what temperature can I decarboxylate the THC, while still preserving the cannabinoids?

Hockey Poo,

When marijuana is harvested, the THC molecule is bound to a carboxyl group ? COOH ? that is, one atom each of carbon and hydrogen and two atoms of oxygen. With a carboxyl group attached, THC is not active.

Heating dried marijuana makes the carboxyl group convert into water (H2O) and carbon dioxide (CO2). When marijuana is smoked, the burning eliminates the carboxyl group. There are several ways to decarboxylate marijuana for use in extracts. A layer of marijuana buds or leaf can be placed in an oven at 150 degrees for 15 minutes. This is far below the boiling point of THC yet warm enough to evaporate the carboxyl group. Another method of releasing the COOH is by placing a bowl of buds in the microwave for 2 minutes. The waves will boil away the water. The boiling point of marijuana’s active cannabinoids ranges from 260-392 degrees F.

The Coldfinger is made by Eden Labs, a company in Ohio that makes several models of herbal extractors, from the simple to the most sophisticated. They can be found on the internet at

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