test kit

[what?]

Hi, the other day i went out for my friends birthday and while out a guy gave my friend, what he said was a crytstal of mdma.
My friend didn't want to take it there, so the guy tried to give it to my other friends but they didn't want to take it either, so in the end he just gave back to my friend as a birthday present.
Now, my friend has been interested in trying e for a while, so they don't want to just throw this crystal away. They were thinking about getting a test kit to see if it was what he said it was.
So, they asked me to ask if anyone could recommend a good testing kit, or some reagent solution.
They're pretty sure the guy who gave it to them was genuine, cause it was quite a small environment, and he tried to give it to others.
What do people think?