A childhood belief about chemistry

I had heard that coal can be made into diamonds. I thought this was because there was a diamond inside every piece of coal.

So I did the only logical thing: rinse off a charcoal briquette in the sink until it became a diamond.

I never stopped to think that, if diamonds were this easy to obtain, why we had a whole bag of potential diamonds in our backyard and yet we weren't millionaires. I thought I had made some sort of fantastic, nobel prize-winning discovery.