I will answer this but then close it as most of you are simply being idiots... you don't stay on topic but instead just flame and flame...
Heroin is cut at two differnt levels -
1) manufacture/pre-distro - this process is not always done in the US, but when the heroin first comes into the country it's often in a highly refined and pure form - DEA reports are saying 98%-99% pure shit, I mean, insanity.. wel, yeah, this could lead to a lot of deaths but I really dont think thatsthe concern ofthose that cut it - it's cut to increase the volume..see, it's easier to smuggle a few pounds of pure ter heroin in, then cut it and have the volumew go through the roof! - again, you COULDNT sell it as-is or uninformed users would die...
Now, what usually happends is this - some pure tasr is smuggled into the US, this stuff is of an ultra purity and compressed very tight so it can be packed inside spanis women and car tires, it get into the US and tossed into a freezer (so it's not as sticky) .. after its been in awhile its pulled and lactose is added - depending on the volume a blender can be used - some of the large operations will actually get realy huge mixers like you see in restraunt movies... after awhile you will have yer powder - it's set under a heatlamp which makes it look all pretty .. often an acetone wash will be carried out too further clean it up...
In other cases, powdered heroin is brough in, disolved in fluid, cut with something (again the origial being like 98% pure) then powdered again..
In both of the above large amounts are hydrolically compressed in "fingers" (whebn using a pipe) or discs, om there it goes to some of the top level dealers and isn't then cut again UNTIL ...
Ricardo bought a gram and is going to sell packets, well, not only does he want the money but he wants to get high... so, he grabs whatever happends to be laying around and steps all over the heroin ...
Next time lets not fight so much... you guys gotta learn to act like ADULTS when you disagree... don't call someone a "stupid fuckity fucking fucker McFuckFuck" but instead carefully dispute with them the error of their ways....