Runner, street slang for base incorrectly refers to the salt, not the freebase. As you know, while the freebase is a white coloured oil, the salt should be crystal if it is relatively pure and dried (free of solvents and H2O)
While colour can always be intentionally added (food colouring, iodine etc) or be present as dyes not removed from certain sources of pseudo, I believe most colour is simply the product of an incomplete or overdone reaction, with little if any purification carried out.
When the hypo/ I2 reduction of pseudo is carried out, the reaction is often described as first turning purple/red then to orange, and finally to yellow. If you go to the place where such things are discussed and look for a bee named SHORTY while searching – Enter: “meth color red” – you will notice this procedure is characterised by colour and smell, both of which change as the reaction progresses.
Because it is claimed a sloppy procedure can give reasonable yields and purity without a need for distillation, it makes perfect sense that many probably do not run the reaction to optimum, add incorrect ratios of reactants, or allow water in the mixture etc. If no distillation and few washes are done, these reaction intermediates, unreacted reagents etc will be in the final product.
A few weeks ago there seemed to be an abundance of red/orange speed around Brisbane. Rumors everywhere were that it was made and put out by the cops so that syndicates could be tracked, busted etc.
While this is possible I guess, it is hard to believe the police would (above board anyway) release something of this quality. It was absolute shit to look at and smell. God knows what that it would do to a person’s liver and kidneys over time!
Although colours may be readily identifiable by field officers, any speed can be linked to another seizure through lab analysis. The levels of impurities are a specific signature of a batch. It would make much better sense for police to release a clear or variety of different coloured batches if they were to do such things. That way, at least their part in distribution would have more chance of remaining surreptitious.
The basic fact of the matter in regards to colour, smell and appearance; is that meth can be cooked by a kid with no chemistry knowledge, in the boot of a car in one pot.
However, the same process can be used by someone concerned enough (and possessing the right knowledge) to produce a product of much higher purity i.e. crystals.