Methamphetamine in its pure xxx form is colorless. However, products on the market today are often not colorless. The following is a table of some common impurities and the colors associated with them. Note: There is no doubt a segment of the dealers who will add food coloring or some other such color to their drug to make it more appealing, with the philosophy that a brightly-colored product may sell better than an off color product. This is relatively uncommon however.

RED: The product was made from XXX, and the red coloring of the tablet was not adequately washed away (it is difficult).
ORANGE: XXX was used, and some of the XXX was reduced to XXX.
PURPLE: XXX from a XXX reaction was not washed out.
GREEN: Copper (or other metallic) salts somehow made their way in to the mixture, probably due to the reaction vessel used in the manufacture.
BROWN: Oxidized red coloring, or tablating agent was present in the reduction.
Sometimes "speed" is present as waxy rocks that almost seem wet, but do not dry out properly. I am not sure what the cause of this is, but its most likely some form of oil, either formed in the reaction or left over from a very poor XXX. It may or may not be harmless depending upon what it is. This oil is often removed with XXX, but XXX would be better suited for this as it dries faster.

Pure methamphetamine HCl melts at around 170c (338f ). The crystals can be carefully chopped and mixed with XXX, and when the resulting powder is heated (and the methamphetamine HCl melts) CO2 and methamphetamine base vapor is given off. This is probably one of the more effective ways of smoking meth if you are careful, however the hydrochloride salt is often the form smoked as the base form is often an oil and is difficult to store, transport, and work with. Smoking the HCl form is OK if you don't mind a small quantity of pyrolysed drug.

The TASTE TEST [illegal without prescription snicker snicker]
Methamphetamine has a very bitter taste. Amphetamine has a bitter taste, followed by some degree of numbness. This isn't the most useful test in the world, especially considering it relies upon subjective senses too much IMHO, but it may help discern the product.

cooking meth is cool especially when the house blows up and the fire trucks and cops show up. All those flashing lights look cool.The jail sentence is the best part though free food and entertainment for 5 to 10 years you don't have to think about nothing its all planned out for you.

Thats the reason why you never have to pay bills the best part is the butt sex.

well to each his own I guess