Two such Methamphetamines are crank and ice.
Crank refers to any form of methamphetamine.
Ice is a crystallized smokeable chunk form of methamphetarnine that produces a more intense reaction than cocaine or speed. Ice has an appearance that is clear and crystal-like, and resembles frozen ice water. Methamphetamines stimulate the central nervous system, and the effects may last anywhere from 8 to 24 hours. Crank and ice are extremely addictive and produce a severe craving for the drug. Info from lifeormeth.org Narconon Centers Throughout the World Information on Marijuana.