Stripped of your "poetic" title, you're basically asking how is deuterium purified away from hydrogen to make heavy water. Here's a wikipedia link to one process: http://en.wikipedia.org/wiki/Girdler_sulfide_process Basically, different isotopes have slightly different physical and chemical properties. By engineering, we can use those properties to concentrate an isotope gradually, and by repeating the process, concentrate further. http://en.wikipedia.org/wiki/Isotope_separation