A childhood belief about chemistry

When I was quite young I believed that if you left glass in the sun long enough, that it would turn into diamonds and crystals (depending on the colour of the glass obviously). I had quite a collection of glass sitting on my bedroom windowsill until one day, my mum threw them all out and told me the horrible truth. I believed for years after that, that they had finally 'turned' and she had taken them for herself and every time she 'bought' new diamond earrings or a sapphire necklace I'd look at them suspiciously.