Hashish

Hashish, or hash, is a concentrate made from cannabis. Hashish can be consumed by smoking in a pipe, bong, vaporizer or joint, or eating it. 
Hash is an extracted cannabis product composed of resin glands, trichomes, from the plant. 

The resin contains tetrahydrocannabinol (THC) and other cannabinoids but often in much higher THC concentrations than the cannabis flower
Pressed hashish is usually solid, whereas water-purified hashish called "bubble melt hash" or "bubble hash is a paste-like substance that can be crumbly. 

Color can be from light to dark brown, yellow, tan, black, or red. 
Besides its recreational use the active ingredient of hashish, THC has been of interest for research and medical purposes

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