Abstract: The resonator for a timepiece includes a support structure permitting mounting the resonator in a timepiece, a first and a second balance arranged to oscillate in the same plane, at least one first and second elastic element respectively connecting the first and second balances to the support structure, the configuration of the elastic elements determining two parallel elastic pivoting axes for the two balances, and the elastic elements forming a resilient element angularly returning each of the balances towards an inoperative position. The resonator further includes a strap coupling the first and the second balance. The points joining the strap to the first and the second balance respectively are located in the same plane parallel to the plane of oscillation of the balances. When the balances are in their inoperative position, these joining points are symmetrical with respect to a center of symmetry midway between the geometrical pivoting axes.

Abstract: The phosphorescent compounds of the invention have a matrix with the general formula M2SiO4 wherein M represents an alkaline earth such as barium, strontium or calcium, and the matrix is doped with europium and co-doped with at least one other lanthanide such as praseodymium, samarium, dysprosium or holmium. In accordance with a method embodiment, the dopant compounds are introduced into the matrix in the form of fluorides by calcination in a reducing atmosphere. The invention may be applied in the field of horology.