You may have seen the PBS Nature program special on Diamonds that first aired back in 2006, or perhaps are aware of this through some other channels, but it caught my attention that there are pink (and a few red) diamonds coming from the Argyle Mines in the Australian outback. What’s really interesting about these million dollars a karat diamonds is why the diamonds are pink. No one knows why. The program was quite clear on what makes other colors (such as boron makes diamonds blue) but they said that the pink baffled everyone.
Now I will admit I know nothing of conditions below the mantle where diamonds form; and diamonds supposedly two to three million years old are from an era definitely out of my sphere of surety -- but I immediately thought of a reason for diamonds to be pink. (I’ll admit from a scientific standpoint it’s a complete cop-out.)