2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179127The mass spectrum of D-wave mesons is considered in a nonrelativistic constituent quark model. The results show a common mass degeneracy of the isovector and isodoublet states of the 1 $^3D_1$ and 1 $^3D_3$ nonets, and suggest therefore that the $K^\ast (1680)$ cannot be the I=1/2 member of the 1 $^3D_1$ nonet. They also suggest that the $η_2(1870),$ presently omitted form the Meson Summary Table, should be interpreted as the I=0 $s\bar{s}$ state of the 1 $^1D_2$ nonet.11 pages, LaTeXHigh Energy Physics - PhenomenologyOn D-wave meson spectroscopy and the $K^* (1410) - K^* (1680)$ problemtext