The thick oil is not highly marketable as an illicit drug because it cannot be easily injected or snorted, and is often associated with vein damage among people who inject it. Therefore, manufacturers attempt to purify methamphetamine base (oil) into methamphetamine hydrochloride (crystal). To successfully complete the process requires considerable chemistry expertise, so the resulting product is often a pasty, sticky powder that has a yellow or brown hue due to the presence of iodine and other organic impurities, and generally requires heating to sufficiently dissolve it for injection. Organic impurities are an indication that the purification process was not performed accurately, preventing the substance from forming into the large translucent crystals typical of 'ice'. Base is not common in Southeast Asia, but is known to be manufactured in Australia. It is usually of fairly high purity.