Methcathinone, also known as ephedrone, is one of the earliest cathinones. Structurally it is beta-keto -methamphetamine and is a schedule I controlled substance. The derivates of methcathinone are more popular and methcathinone by itself is currently not encountered often in street drugs.
Additional reading:
Methcathinone Wikipedia Article
Overall recommended test:
The microcrystals formed by methcathinone are very small and difficult to study by IR microspectroscopy. For a standalone microcrystal test, either reagent may be used.