When I was about 11 or 12 I bought 3 fifty pound bags of KNO3 for a grand total of $9.00. My oldest brother bought me a blower that I used to grind the prills. I put a funnel in the intake and a double pillowcase on the out side. If you ran the prills through twice is was like dust. The blower had many blades just like a jet engine and in fact it sounded sort of like one when it spooled up. If you lifted it and tried to turn it, you could feel the force like a gyroscope.
I made a lot of little rockets and one time I lit an entire large coffee can of KNO3 and sugar. I thought the police would come the cloud went so high up in the sky, it was kind of spectacular. I got my gunpowder to burn pretty fast too, in a quick poof.
Back then, you could buy 75% calcium hypochlorite pool chlorine and it would spontaneously ignite with sulfur after a bit or if you put a drop of water on it, it would start quickly. Or you could try various oils or other odd things like Cox glow fuel. The off-white granules would then turn a bright orange and then burst into flames, calcium making a pretty red color. And about 10 years ago or so I bought a 50 pound bag of NH4NO3 for 6 dollars about a mile from my house at a garden store. WIth that you could mix it with pool chlorine and it would crackle and pop fiercely creating rapid fire firecracker type sounds and looking something like popcorn gone crazy as particles fly about ejecting off the pile; sometimes I would put it in a can instead of on the ground. It made a fair amount of smoke you probably wouldn't want to breathe. If it didn't start on it's own after a minute you could wet it to get it started. With powdered zinc, ammonium nitrate will also catch fire. I remember the prettiest color smoke I made using these two ingredients and iodine crystals. Iodine smoke is very vivid and with the NH4NO3 it really adds to the effect. Imagine a billowing smoke that is intensely blue transitioning to some kind of indigo violet as it cools, the smoke looks soft almost, it's hard to describe.
But then I guess I grew out of that phase, playing with sodium and such. Once you do all the neat experiements you can find, it's kind of no fun to keep repeating the old ones. And today it seems things are getting more and more controlled. Iodine and ammonium hydroxide make a classic super sensitive explosive a fly can set off, yet both these chemicals raise eyebrows these days, maybe get your name on a government list. Oh!
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