Froehde Reagent Color Chart: How to Read Results
What each Froehde reagent color means: MDMA and MDA turn blue-black, amphetamines give nothing, PMMA turns light green. Full chart and how to read it.
August 11, 2026 · Jordan Mercer
Froehde is the third reagent, not the first. On its own it answers almost nothing. MDMA and MDA both turn a blue-tinted black, amphetamine and methamphetamine give no reaction at all, and PMMA gives a very light green that is one of the more useful red flags in a home kit. What Froehde buys you is a third chemically independent opinion on a result you already have.
The color chart
Froehde is a molybdate salt in concentrated sulfuric acid, and it reads fast. Judge the reaction inside the first 45 to 60 seconds. Every reagent drifts dark on its own eventually, so a slow creep to brown after several minutes is not a result.
These are the expected reactions from DanceSafe’s current instruction pamphlet.
| Substance | Froehde color |
|---|---|
| MDMA | Blue-tinted black |
| MDA | Blue-tinted black (looks the same as MDMA) |
| Amphetamine | No reaction |
| Methamphetamine | No reaction |
| Cocaine | No reaction |
| Ketamine | No reaction |
| PMMA | Very light green |
| 2C-B | Bright yellow through olive to near-black, often with a yellow ring |
| 2C-I | Amber through to very dark maroon-black |
| Mescaline | Olive-yellow to mustard to amber-brown |
| Heroin | Pink to deep purple |
| Oxycodone | No reaction, light yellow, or sky blue |
| Mephedrone (4-MMC) | No reaction |
| 5-APB / 6-APB / 5-MAPB / 6-MAPB | Purple to black |
| LSD | Faint pale gray to slate (Ehrlich’s is the LSD test, not Froehde) |
| Sugar and inert fillers | Pale cream to tan, easy to mistake for a weak reaction |
Blue-black means a methylenedioxy compound, so MDMA or MDA. Nothing at all rules that class out. Light green is the PMMA warning, and PMMA is the substitute that kills people who redose because their pills felt weak.
None of these colors carry dose or purity, none of them can tell you whether a second substance is hiding under a dark reaction, and no reagent sees fentanyl at all.
Marquis, then Simon’s, then Froehde
Marquis reacts with a broad range of phenethylamines, which is why it goes first. Froehde is narrow. It gives strong distinctive colors with a handful of substances and nothing with several very common ones, including cocaine, ketamine and both amphetamines.
The narrowness is the point. If Marquis went purple-black and Simon’s went blue, you already have a good MDMA read, and blue-tinted black on Froehde means a third test with different chemistry agrees. Light green instead, or nothing at all, means the story you built from the first two has a hole in it.
Backwards, it falls apart. No reaction on Froehde is consistent with cocaine, ketamine, meth, amphetamine, mephedrone and a jar of inert powder. That set is far too wide to act on. Froehde narrows things only when there is another result to combine it with.
For an ecstasy or molly sample, DanceSafe’s published order:
- Marquis goes black, sometimes purple or brown at the edges, for both MDMA and MDA.
- Simon’s separates them. Blue for MDMA. With MDA it either does not react or turns a muddy gray-green. Details in MDA vs MDMA.
- Froehde confirms, blue-tinted black for both.
- A fentanyl test strip, every time. Dissolve in 1 teaspoon (5 mL) of water per 10 mg, or 2 teaspoons (10 mL) for MDMA and methamphetamine, before dipping, or you will get a false positive from the concentration alone. One line means fentanyl is present and two lines means it is not, which catches people out constantly. Method in our fentanyl test strip guide.
For an amphetamine or meth sample it is Marquis, Simon’s, then Froehde as an optional extra. Marquis turns orange for both, Simon’s turns blue for meth and does nothing with amphetamine, and Froehde gives you nothing, which is the expected result rather than a failed test.
Running it, and the ways it goes wrong
- Crush a small sample onto a clean white surface. Roughly 10 mg, about a match head, on ceramic, porcelain or hard white plastic. A ceramic spot plate stops separate tests bleeding together. Fresh sample per reagent, never a second reagent onto a used spot. If your sample is mostly cut, remember sugar reads pale cream to tan here, and you may be looking at the filler rather than the drug.
- Add one drop, without touching the dropper to the sample. That contaminates the entire bottle. Do not rest the cap on a surface or on the wrong bottle either.
- Put a second drop of reagent on its own, next to the test spot. Reagents are tinted and darken with age, and this blank is the easiest way to see whether anything actually changed.
- Watch the first minute. Note the color at 5, 15, 30 and 45 seconds, since speed matters as much as the peak color. Anything that only turns dark at three minutes is age, not a reaction.
- Read under white light against the printed chart. Dim or colored lighting is the single most common reason a color gets called wrong.
- Neutralize with baking soda, wash, dry fully. Reagents are corrosive. Wear gloves.
Two habits of mind matter more than any of the steps. No reaction does not mean clean, it means Froehde did not find the thing Froehde reacts with. And blue-black does not settle the question, because it fits MDMA and MDA equally, tells you nothing about how much of the powder is active, and cannot see fentanyl.
Read it in the first minute, under white light, beside a blank, and only after Marquis. Blue-tinted black points at MDMA or MDA, no reaction rules that class out, light green is the PMMA stop signal. You can pick up the DanceSafe Froehde reagent on its own or as part of a multi-reagent set. The full walkthrough is in how to test your MDMA, and for dosing and safer-use practice see the MDMA harm reduction guide.
Color reactions above are the expected reactions published in DanceSafe’s reagent testing instruction pamphlet (version 17, spring 2024) and DanceSafe’s reagent reaction update notes.