We study polarization singularities produced deliberately by preparing optical beams in Poincare′ modes. We present the production of an asymmetric type of C-points, known as monstars. This type of C-point can be produced by the superposition of two beams, one with an asymmetric optical vortex, and a second one with in a fundamental Gaussian mode, both in orthogonal circular polarization states. Experimentally we accomplish this via a polarization interferometer and a spatial light modulator. © OSA 2013.