The fusion fuel used by the bomb was 95 % enriched Lithium isotope 6 lithium deuteride , which at the time was a scarce resource , this scarcity being chiefly responsible for its limited deployment . The Castle Bravo test showed that unenriched Lithium isotope 7 functioned as well for nuclear fusion reactions as isotope 6 . The Mk-14 bomb had a diameter of and a length of . They weighed between , and used a parachute
Castle Bravo
Castle Bravo
Mark 14 nuclear bomb