The road to Ice age straight and simple
The road methamphetamine has taken to become one of the world's most notorious drugs has been a fairly straightforward one.
In the 1970s, the hippie scene gave way to a new trend of popping uppers and shooting up speed.
Motorcycle gangs such as the Hell's Angels were notorious for producing amphetamines using a chemical normally used to clean swimming pools - phenyl-2-propanone (P2P).
In last month's customs raid in Kwai Chung, investigating officers said the drug syndicate had obtained P2P to help make the methamphetamine.
Senior Superintendent John Lee Cheung-wing, the head of the Drug Investigation Bureau, said it was possible the chemical had been smuggled into Hong Kong. But using P2P is an outdated way of producing methamphetamine.
In 1980, P2P was placed under federal control in the United States, but it was soon discovered that speed could be made using readily available ephedrine - which can be extracted from a number of cold remedy medicines. However, this discovery came with a bonus - this speed was not amphetamine, it was methamphetamine, and it was twice as strong as its P2P-derived cousin.
Methamphetamine can be produced by a number of methods. All involve ephedrine or pseudoephedrine. The entire process can require as many as 32 different chemicals.
It is not an exact science but large-scale operations are more likely to use a methodical and exact approach to make crystal meth.
Methamphetamine is a synthetic amphetamine or stimulant produced in pill, powder, liquid or crystal form. The crystal form resembles ice, hence the slang name for the drug.
Ice is almost pure and therefore produces an intense sensation for the user. It is a potent stimulant, drug, which speeds up the activity of the central nervous system. Users could go without sleep for three to 15 days.