Marquis Reagent is commonly sold as "ecstasy testing kits". It is also used by law enforcement agents to do spot checks for opiate drugs (and, presumably, they now also probably use it to test for MDMA, amphetamines, etc). I was given the opportunity to do some experiments with donated material to see how it would react with some of the various unscheduled chemicals which are currently in circulation. Some of these, presumably, could concievably end up on the black market being passed as MDMA or as MDMA adulterants (DXM has already shown up). In particular it wouldn't surprise me to see some chemicals of the piperazine family show up - perhaps BZP or BZP in combination with TFMPP (unfortunately the only piperazine I had access to test was BZP HCl).
This material has been given to Erowid, who maintain an Ecstasy Test Kit FAQ, but I figured I would post it here as well. Make what use of it you will. If anyone does any further experiments into Marquis reagent reactions with other chemicals, I'd be interested in hearing the results.
2C-T-2: Orange to Red (usually a sort of a salmon color)
2C-T-7: Orange to Red (salmon, again; also, there is less tendency towards orange than 2C-T-2 shows)
4-Acetoxy-DIPT: Dirty (blackish) olive
5-MeO-DIPT: Fizzes then turns yellow quickly changing to a slightly rusty orange
Alpha-Methyl-DIPT: Fizzes then turns brown
Alpha-Methyltryptamine: Dark brownish-yellow
Benzylpiperazine: No color change, but it causes the reagent to fizz. Looks like when you pour hydrogen peroxide on a cut.
Diisopropyltryptamine (DIPT): Fizzes strongly then turns a neon yellow
Dipropyltryptamine (DPT): Dirty olive
Harmine: Fizzes slightly, much less so than BZP, and turns a brown-orange rust color.
Yohimbine: Fizzes slightly, much less so than BZP. Slowly (up to a minute), it will turn an olive green color.
