There is no such thing as synthetic cannabis, only synthetic cannabinoids. People were saying Spice had a near identical effect as cannabis and they were correct in my experience, but it didn't seem to have a ceiling. In any case they are cannabinoid agonists so they are behaving similar, but not really much of a safety factor compared to cannabis as a result of the ceiling being much higher. It is possible to actually overdose on this stuff.
I do know for sure you can get synthetic cannabinoids in those bottles like what you had pictured even though some are now illegal, same with a plethora of other weird drugs. There are a number of websites which discuss this material. I would be cautious of anything that did not taste like cannabis and had crystals swimming around in it, like the picture you posted. Do a search for 'synthetic cannabinoid e-liquid'. Looks like the stuff goes for about $20 per 5 mL bottle like you pictured from a quick search. And that is in shops. Online it is probably $10 per bottle.
I will tell you right now that is VERY likely what you have. I haven't used any for for about 7 years but I was real curious so I tried it out when it was new, and then later got some near pure JWH-018 which I would use for a no odor experience. Dosed right it did not feel any different than a cannabis strain. Red eyes, helped with pain, increased hunger, increased humor, helped with sleep, etc. The first time I tried it I was convinced it had some kind of cannabis extract in it. It did not, whatsoever. It really was all it was cracked up to be.
Erowid is a good site for basic info, they have a section on cannabinoids as well as one on 'Spice Product". But do search synthetic cannabinoid e-liquid or synthetic cannabinoids propylene glycol, polyethylene glycol, vegetable glycerin and see what pops up.
You never answered if it tastes like cannabis or not. Obviously nowadays these guys can add terpenes, but if they don't it should have very little flavor or taste, unless flavoring was added.
Be safe my friend. That's messed up if people are trying to pass off cannabinoids as cannabis.
This is the thread the OP posted with pics:
http://fuckcombustion.com/threads/should-thc-e-liquid-be-transparent.21330/
