Acrylic Replicas Restorations in glass have proven to be very costly due to the time and labor required to machine, grind, and polish these large lenses and prisms. Alternative materials have been tested. Acrylic has the closest properties to the original crown glass that was used in the 1800's. This photo shows an acrylic bullseye lens mounted inside one of the original glass bulleye rings. Acrylic Restoration |