In this paper, we show that it is possible to build a polarization splitter from a pair of commercially available geometrical phase lenses. This optical component splits an incoming beam into two circularly polarized beams, with a separation angle that can be varied by a simple translation or rotation adjustment. Our experiments show that excellent polarization separation is obtained with separation angles ranging from nearly zero up to 120mrad, and for wavelengths ranging from 532nm up to 780nm. The measured properties of this new component are well described by a simple analytical model. However, unlike conventional Wollaston prisms, this component exhibits a very large dispersion with wavelength. It can also be described as a polarization grating with adjustable dispersion.