Abstract: A process for manufacturing mirrors comprising notching the backside of a plate and etching it from one or both sides. The front side is plated and polished to a flat mirror-like-like surface. The plate is made from glass rods that have been fused together in a bundle and then heated and stretched. One of the glass rods, near the center, is being susceptible to etching while the others are not. Therefore, when the glass rod bundle is drawn out, they will neck-down and become very fine. When the center glass rod has been drawn down to, for example, about five mils in diameter, the neck of the bundle is harvested for the above plates, by slicing out wafers at an angle, e.g., 45.degree.. The etchants will attack the center glass rod, but not those that surround it, due to their chemical properties. The result is a very sharply formed aperture hole of any desired diameter.