Heroin Common Cutting Agents for Black Tar

So lately I've been getting some black tar heroin from a new connect and it's different than my last. My last guys was powder that would solidify if breathed on and was BOMB, very potent. Then this new guy has a "shatter" consistency (like a thick piece of black glass) and it tastes very funky, TBH. But when it burns down (I smoke it due to lack of availability of syringes in my area) there is a red substance that separates from the black heroin and it kinda looks like when you add creamer to coffee but it's a dark red/brown color. Does anyone know what this could be?

And with that if anyone knows common agents that people use to cut black tar heroin and what kind of taste it gives it or effects etc. Basically if anyone knows what is giving my heroin this red tinge of color and this extra chemically/mediciny taste I'd really appreciate it.
Thanks in advance everybody!!

I think the last stuff you were getting was likely not tar .. while the new stuff is likely tar. Tar is cut with a whole mess of stuff.. its not uncommon for generic cola soda to be a large part of the cut. It can also be cut with a whole range of substances, like cough syrups. (hopefully not codine) Since we will just be providing speculation on this and it falls under identification of unknown I'm going to close this.

Please feal free to PM me or any of the good mods here with any questions or concerns regarding this closure.