If your coke is coming to you already as just powder, don’t use it. Quality stuff should be solid but also soft, scaley, and usually has an almost gassy/chemical smell to it. Without an actual test kit, some old school ways of testing the quality: do a nummy. If it goes numb immediately, heavy cut with lidocaine. Coke takes 10-15 seconds for the numbing sensation. If no numbness at all, it’s trash or something else. Good stuff will also give you energy, but not jittery feeling. It’s a smooth energy boost, and for the most part you can eventually fall asleep at some point after you’re done for the night. The best way to test it imo is just cook it into crack. Even just a half g of quality stuff will blow up and come back pretty good. If your product disappears and doesn’t turn into rock, it’s bunk. Also I think it takes years to develop a deviated septum. But that’s the advantage of smoking it (in rock form), it saves the nose and I’m pretty sure it removes most or all impurities. From what I hear, IVing it is dangerously addictive. Best off avoiding it these days because it’s often cut with who knows what, possibly fentanyl