Permanent reproductions and formation method therefor

Permanent gray-scale reproductions including half-tone images. A refractory background region bears refractory thin-film dichroic filter means patterned to conform to the reproduced half-tone image. Preferred background region materials include metals, semiconductors, and ceramics; the thin-film materials are preferably oxides or nitrides of metals and semiconductors. If the refractory materials are appropriately selected, the reproductions are highly resistant to chemical and thermal deterioration and should have useful lives in the hundreds of thousands of years.