ali_cat-factor 10 said:
with coke is there any quick quality tests one can do besides racking up abit before purchase [only with a v. nice dealer] i.e apparence/taste etc.. i've heard that quality coke kind of shimmers.. anything else? x a.
In short no.
The Scott test is considered a fairly sure positive that cocaine is present, however as it stands, this test alone will not give a quantitative result (how much coke/ impurities are present).
The test uses 3 solutions:
A: Cobalt thiocyanate in water and glycerine.
B: Concentrated Hydrochloric acid
C: Chloroform
If cocaine is present, it will turn Sol A blue. Other things such as Patchouli oil and Caffeine will also turn cobalt thiocyanate blue.
If Solution B is added, the solution will turn a pinkish clear colour. When Solution 3 is added, 2 layers will form and if cocaine is present it will appear in the chloroform layer - again as a blue colour.
The most commonly used (user) tests for cocaine purity include:
* Melting point test of the HCl salt (normal cocaine powder)
* Solubility in water - all should dissolve easily ( 1 gram to ~5mL of cold water)
* Freebase preparation - weight variation to salt (some minor calculations required)
Details on these techniques have been posted before (use the search engine)
It's also worth noting that appearance, smell and taste can be useful in the hands of someone experienced, but at best, a sense derived guess usually only gets a ball park estimate (+ / - 10% tops).
The best advice for obtaining a more pure product? I'm not sure there is any. But it helps if you know someone who only uses occasionally, buys near the top of the chain, and who also isn't too money hungry. (mmm.. are there such people?)
As for appearance; depending on what solvents are used to crystallize the coke (and impurities from various methods of extraction/ processing) the crystal may resemble mother of pearl, or it may be chunky, or just a powder. Hard lumps and various crystal forms can be accomplished by pressing techniques and so don't always indicate a pure product.
Something extra:
Many people speak of the perfect (undetectable) cut being a local anesthetic with similar physical properties.
For those interested in being able to ID some of these agents, the following is taken from the - sadly out of print - bible of Thin Layer Chromatography:
Thin Layer Chromatography: A Laboratory Handbook - Edited by Egon Stahl 2nd Ed
page 554
"The local anaesthetics may be detected on adsorbent layers prepared with fluorescent additives, by illumination with short wave UV light [63]. Reagents which can be used for visualisation are: 4-methylaminobenzaldehyde solution (Rgt. no 72) [27, 63]; Dragendorff reagent, prepared in various ways [63, 141, 159]; iodine-iodide solution (Rgt. No 144) [141]; and a 0.5% solution of Fast Red GG in water [159]. Meprylcaine, which does not react with the dragendorff reagent, can be located by spraying with a 5% aqueous solution of sodium nitrite [159]...."
Numbers in square brackets refer to intext references, numbers in round brackets describe reagents as listed in the handbook.