Read the link provided by Tricomb, and check out this thread for information on micron filters.
Obviously, we cannot tell you with certainty what it is you actually purchased, even if we did allow Drug ID's here. There is also no way to know whether it's "clean" or not either. It's a street drug. The safest bet is always to not do it, the second would be to not inject it, and the third would be to make sure to do a test dose via insufflation, and then to micron filter the heroin and inject it with a fresh syringe.
That being said, I will close this. Please look at the links provided. If there are further questions you are free to PM me at any time.