Black......then purple??

[Don Juan]

I recently got an EZ test so I
tested it with a pill that I had
already taken and when the agent
touched the substance it fizzed
and in less than a second it went straight to black and then after
6 sec. to dark purple.
Is that common , or could it mean
that the pill might be strong or
weak??

 

[aj]

Fizzing and straight to black ?
Sounds like it contains an Ecstasy like substance.
Weak or strong ? Impossible to tell with current testkits.
aj

 

[Soma]

One theory:
Remembering that the 'black' can be seen as many layers of purple...
When you start the reaction, the pool of reacting liquid tends to ball up with the gas escaping upwards, to make the bubble liquid is drawn from underneath. As the reaction slows and everything spreads out and the liquid thins also because of gravity, the purple hue can come come out especially around the edges.
Think of it this way, if you had a bucket full of dark purple liquid, the bottom of the bucket would look black - throw that liquid over a large white surface floor (ie spread it out), it looks purple.

 

[Don Juan]

Aj & Soma thanx for the explaination. And yes Soma after
the initial fizzing and the deep
black stage you defenitley can
see the purple especially, like
yo said around the edges.