Just because coke looks like "fish scales" and its crystalline doesn't necessarily mean its uncut or even good. Nowadays they can reconstitute it to make it look just like that. The coke around nowadays is nothing the the old stuff- today they cook up such massive amounts at a time they don't spend the extra time to do it right. It always rushed and usually cooked by amateurs not chemist. Not to say you still cant get good coke it just takes time to find it- most people never see it. It helps to know the right people also. Just for a reference I'm talking from experiences in CA.
Why would anyone go through that process with baking soda and the like? Mix powder in water, drip a bit of ammonia in there. Pour into filter paper, drip some fresh water over it and let it dry. Better yet.... dont do it