Osmium, an obscure metal, was once the go-to material for phonograph needles, back in the early days of recorded music when 78 RPM discs made of wax were in vogue. Once wax gave way to vinyl records, osmium fell out of favor, and styluses were made from sapphire or diamond.

However, levels of the relatively rare element appear to be rising in the environment--it's produced by the platinum-refining process used to make catalytic converters in cars.