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1. Macroscopical, Microscopical, Organoleptic characteristics.

2. Chromatography: TLC, GC, HPLC, using reference samples.

3. Chemical tests:

1. Modified Beam’s test:

The Beam test is relatively specific. It gives a purple color with 5% ethanolic KOH, based on the
oxidation of CBD, CBG, etc., and their acids to hydroxyquinones. However, THC does not react to
the Beam test. A modification of the Beam test uses absolute ethanol saturated with gaseous
hydrogen chloride. When added to an extract of suspect material, it gives a cherry red color which
disappears if water is added.

2. Fast Blue B Test:

Place 1 mg of cannabis on the upper side of sheets of filter paper. Add light petroleum (40-60 oC)
drop by drop until the lower paper is just moist. Remove the upper paper and add to the lower
one part of Fast Blue B reagent, a red to violet colour is developed.

Morphology of Cannabis Leaf Cannabis, A: Bract and its pair of bracteoles, each
with a female flower in the axil, B: Simple

lanceolate bract, C: a ternate bract, D: pistillate
flower, b: bract, bl: bracteole, fl: flower, o: ovary,
ov: ovule, pg: perigone, sp: stipule, st: style and
stigma.

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