The MAGIC Telescope has the largest reflecting surface, among other Cherenkov detectors, in order to have an energy threshold well below 100 GeV. In this contribution, we describe the technology used for the production and the optical qualities of the surface currently mounted onto the telescope. MAGIC features now 964 square mirrors, 50 cm by side, each of spherical shape. We present also a new technology that, producing pre-shaped panels, will finally yield lighter mirrors and can even be applied to make bigger mirrors of 1 m by side.