Color of Amphetamine Sulfate

[Mdp2p]

Why is black market amphetamine sometimes yellow? And when it has a pink tone?

 

[Hest]

Because its full of junk. In the old days people where adding pH indicator when making the salt, resulting in usual pinkish color (from phenolphthalein).

Salts from small bio-active amines are either huge transparent crystals or a white powder.