The Marquis reagent on its own is colorless. It’s best to use Marquis reagent to test MDMA, MDA, 2C-B, cocaine, meth/amphetamine, or opioids, but it’s also a good test for benzofurans, cathinones, tryptamines and phenethylamines.
NOTE: Marquis can only test the PRESENCE, but not QUANTITY of a specific substance.
Always test under a strong light and using the smallest possible sample. Never open more than 1 bottle at once, if you make a mistake you might contaminate the reagents and spoil them. If a few reactions are happening at once, only the darkest one of them will be visible. To detect adulterants, try using on fresh samples secondary reagent tests like Robadope, Simon’s, Scott or Zimmermann. If you don’t know yet how to use Marquis reagent, see the following instructions:
- On a clean ceramic surface (e.g. bottom of a mug or a plate) prepare a sample no bigger than this size -> ●
- Carefully not to touch the sample with the bottle, remove the cap, twist the bottle upside-down and wait for 1 drop to fall. Replace the cap.
- Immediately observe the color change and compare it with the Marquis color chart. No reaction within the first 30 seconds or unexpected results indicate the sample doesn’t contain the expected substance or is adulterated.
- Neutralize the reaction with baking soda (optional) and flush in a sink under running water for a few minutes.
No reaction can be caused by PMA/PMMA, mephedrone, cocaine, caffeine and other substances (or lack of active ingredient). CHECK TESTDRUGS APPS – TestDrugs.info
Common Marquis color reactions:
- 2C-B – yellow to green (needs Robadope test)
- DMT – orange (needs tests Ehrlich and Hofmann)
- DOC / DOI – green (needs Robadope test)
- DXM – slow grey to black
- MDMA / MDA – immediate violet to black (needs tests Simon’s and/or Robadope)
- MDPV and more cathinones – yellow (needs tests Zimmermann and/or Simon’s)
- Meth/amphetamine – orange (needs tests Simon’s and/or Robadope)
- Codeine / Morphine / Heroin – purple
Find the best reagent test kits HERE. Next choose a purity testing kit. They can detect all adulterants at once, but still require reagent tests for identifying ingredients.
- To estimate purity of a substance (amount of adulterants and potency) use Substance Purity Test Kit.
- To precisly estimate MDMA potency use MDMA Purity Test Kit, which additionaly contains a calibrated plastic measuring tool.
Click HERE to download the Marquis reagent color chart in full resolution.
PAUL
16 October 2025 @ 01:28
The instructions are horrible. The marquis and other reagents are in powder form and your instructions say to add one drop. How do I get one drop of powder? It seems the powdered reagent needs to be mixed with a liquid but this is nowhere that i can find in the instructions. What liquid to mix it with in what proportions? How can your instructions not oblige this step. i need to do tests now. Please explain to me. i have never paid for anything with such absolutely useless instructions. Very disappointed.
Jerzy Afanasjew
17 October 2025 @ 10:35
Hi Paul, this page is indeed temporarily out of date but please see instructions included in your kit, they are very comprehensive. You can also check https://protestkit.eu/how-to-use-crystalline-reagents/ or our new booklet https://protestkit.eu/protestkitbooklet.webp (chart at the end is not finished yet but there are tons of useful references anyway. I hope this helps! Feel welcome to reach out to us directly via Telegram / Signal / WhatsApp for a more hands on assistance. We are always happy to help. Kind regards, Jurek @ PRO Test, Chemical Safety sp. z o.o.