Creating A Marijuana Tincture Using Alcohol Extraction:

                            The Heated Method

1. Finely grind the marijuana. A standard blender works fine for this, although you can chop or crumble it as you see fit.
2. Preheat your oven to 225 F (110 C). Do NOT exceed 300 F (150 C) to prevent letting your precious THC vaporize!
3. Place the crumbled marijuana in the oven-safe container, and bake for 45 minutes. 30 minutes will often suffice, but if the container is rather thick-walled, it will take some time to come up to temperature.
4. Remove the container from the oven and let it cool for 1/2 hour.
5. Next, place the “baked” (decarboxylated) marijuana into the mason jar/glass, crumbling more if necessary. Gently pour in 1 cup of 70% grain spirits, and stir thoroughly.
6. Seal the jar and shake it. You’ll notice a change in color almost immediately, and this will develop into a deep, almost black-hued green color over the next couple of days.
7. Shake the jar containing the alcohol/cannabis mixture several times a day for at least two days. There’s no need to wait a week or more, THC is quite soluble in alcohol. The waiting time does allow all the bits of marijuana to become saturated and the THC to go into solution.
8. Strain the alcohol/cannabis mixture through a funnel lined with cheesecloth and into a large enough receiving jar. Ball up the cheesecloth and squeeze out more of the solution – waste not!
9. Transfer the tincture into brown glass dropper bottles for storage and dosing. If you can’t get dropper bottles, just brown medicine glass bottles will do – the brown glass helps prevent light from degrading the tincture.
10. Store the finished tincture in a cool place away from strong light sources for maximum shelf life.

Cold Method (recommended)

Here is the recipe for highest quality tincture. This method does not use heat so keeps the integrity of the cannabinoids intact.  FromWAMM

• Fill jar ¾ full of herb
• Fill rest of jar with alcohol; leave some room at top, stir.
• Shake jar [vigorously] one or two times a day  for 2 weeks [or leave it until there is no green color left in the plant matter]
• Strain through metal tea strainer or silkscreen.

You can use whatever kind of clean glass, not plastic, jar you have with a tight lid. One-quart mason jars are ideal. Grind the herb thoroughly in a blender. It should be well ground but doesn’t have to be a powder. You can use leaf, bud, shake, joint leftover, or stems. Too many stems will wreck your blender and make a weaker tincture. Leaf will work fine but for higher potency use shake or bud. Fill the jar ¾ full of herb; it does not have to be exact. You can use anywhere from ½ to 2/3 part herb but ¾ will make a full strength tincture. Use the highest proof alcohol you can, Everclear, which is 180 proof, but hard to find. So just use the highest proof Vodka you can find. Pour alcohol over the herb, filling the rest of the jar. Leave just enough space (an inch or so) at the top so that you will be able to shake the jar. Stir the mixture; the herb will absorb some of the alcohol so you may need to add more. Put the lid on tightly; label the contents and the date you started. It takes two weeks for the alcohol to extract all the active elements from the herb. Shake the jar once or twice a day for 2 weeks. The alcohol will rise to the top and a deep green/red color will develop. After 2 weeks of aging you can strain the tincture through a metal tea strainer or a silk screen into a small tincture bottle with a dropper. You can leave the rest in the jar if you want, it will age and mellow in flavor and you can strain off as much as you want at a time. Alcohol is a strong preservative it will hold for a long time, be careful when handling the tincture, it satins and will turn everything it comes in contact with green. Use Ultra Palmolive anti-bacterial dish soap, the orange kind, to clean the glass, metal or other ceramic utensils, (do not use plastic) sinks and counter tops works best at dissolving THC residue.

Dosage varies per individual but start with half a dropper dissolved in hot tea or water. Hot tea will dissipate some of the alcohol and activate the THC a bit. It can be taken straight but may burn the tongue and has a very strong herbal taste. [If you cut it with equal parts water, you can hold the dosage under the tongue without burning. Takes effect in seconds.

sources:  http://patients4medicalmarijuana.wordpress.com/
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