An excess amount of ${}_{}{}^{96}{}_{}{}^{}\mathrm{Mo}$ found in a 1.7×${10}^9$ yr zircon sample from Cable Sands’ Western Australia, yielded a half-life of (3.9±0.9)×${10}^{19}$ yr for the double beta decay of ${}_{}{}^{96}{}_{}{}^{}\mathrm{Zr}$ to ${}_{}{}^{96}{}_{}{}^{}\mathrm{Mo}$.

• Received 26 February 1992

DOI:https://doi.org/10.1103/PhysRevC.47.R2452