  We show that metastable ring-shaped clusters can be constructed from
two-dimensional quantum droplets in systems described by the Gross-Pitaevskii
equations augmented with Lee-Huang-Yang quantum corrections. The clusters
exhibit dynamical behaviours ranging from contraction to rotation with
simultaneous periodic pulsations, or expansion, depending on the initial radius
of the necklace pattern and phase shift between adjacent quantum droplets. We
show that, using an energy-minimization analysis, one can predict equilibrium
values of the cluster radius that correspond to rotation without radial
pulsations. In such a regime, the clusters evolve as metastable states,
withstanding abrupt variations in the underlying scattering lengths and keeping
their azimuthal symmetry in the course of evolution, even in the presence of
considerable perturbations.
