The Mandelin reagent is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It is composed of a mixture of ammonium metavanadate and concentrated sulfuric acid. Its primary use is for the detection of ketamine and PMA [1] Unlike the most common reagent test chemicals, it has a deep red colour that changes to yellow if there is no alkaloid, which occurs within about 48 hours of mixing. [2]
The United States Department of Justice method for producing the reagent is the addition of 100 mL of concentrated (95–98%) sulfuric acid to 0.5 [3] -1 g of ammonium metavanadate. [4]
This reagent was invented by the German pharmacologist, Karl Friedrich Mandelin (1854–1906) at the Imperial University of Dorpat.
| Substance | Color | 
|---|---|
| 2C-T-7 | Wine dark to Black [5] | 
| Acetaminophen | Moderate olive | 
| Benzphetamine | Brilliant yellow green | 
| Chlorpromazine | Dark olive | 
| Cocaine | Deep orange yellow | 
| Codeine | Dark olive | 
| d-Amphetamine | Moderate bluish green | 
| d-Methamphetamine | Dark yellowish green | 
| Diacetylmorphine (Heroin) | Moderate reddish brown | 
| Dimethoxymethamphetamine | Dark olive brown | 
| Doxepin | Very reddish brown | 
| Dristan | Greyish olive | 
| Exedrine | Dark olive | 
| Ketamine | Deep reddish orange [1] | 
| Mace | Moderate olive green | 
| MDA | Bluish black [6] | 
| MDMA | Bluish black [6] | 
| Mescaline | Dark yellowish brown | 
| Methadone | Dark greyish blue | 
| Methaqualone | Very orange yellow | 
| Methylphenidate | Brilliant orange yellow | 
| Morphine | Dark greyish reddish brown | 
| Opium | Olive black | 
| Oxycodone | Dark greenish yellow | 
| Procaine | Deep orange | 
| Propoxyphene | Dark reddish brown | 
| Psilocybin | Green [7] | 
| Paramethoxyamphetamine (PMA) | Reddish brown [1] | 
| Paramethoxymethamphetamine (PMMA) | Reddish brown [1] | 
| Salt (NaCl-HCl) | Strong orange |