The [Y/Mg] clock works for evolved solar metallicity stars D. Slumstrup, F. Grundahl, K. Brogaard, A. O. Thygesen, P. E. Nissen, J. Jessen-Hansen, V. Van Eylen and M. G. Pedersen A&A, 604 (2017) L8 Published online: 09 August 2017 DOI: 10.1051/0004-6361/201731492