Goldstone (glass)

Goldstone is a type of glittering glass made in a low-oxygen reducing atmosphere. The finished product can take a smooth polish and be carved into beads, figurines, or other artifacts suitable for semiprecious stone, and in fact goldstone is often mistaken for or misrepresented as a natural material.

Another common name for the material is aventurine glass, based on the original Italian name avventurina (from avventura, "adventure" or "chance"). It is also sometimes called "stellaria," "sang-e setareh" or "sang-e khorshid" (sang means 'stone', 'khorshid' means 'sun' and setareh means 'star' in Persian) for its starry internal reflections, or "monk's gold" or "monkstone" from folkloric associations with an unnamed monastic order.

The material is sometimes called sandstone when used in watch dials, despite its lack of resemblance to the porous, matte texture of the natural stone.

Curiously, "aventurine" glass is one of the few synthetic simulants to provide the eponym for the similar natural stones. The mineral name "aventurine" is used for forms of feldspar or quartz with mica inclusions that give a similar glittering appearance; the technical term for this optical phenomenon, "aventurescence," is also derived from the same source.

One original manufacturing process for goldstone was invented in seventeenth-century Venice by the Miotti family, which was granted an exclusive license by the Doge. Urban legend says goldstone was an accidental discovery by unspecified Italian monks or the product of alchemy, but there is no pre-Miotti documentation to confirm this. A goldstone amulet from 12th-century Persia in the collection of the University of Pennsylvania shows that other, earlier artisans were also able to create the material.

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