Scrap gems to diamonds.

[allen]

I don't recall ever seeing a parcel of Zircons that were not "paper worn" to some degree. One of the main reasons I always avoided using them in jewelry.

[Barbra Voltaire, FGG]

Wee Google search.
early 40's w/g blue zircon ring/ Crisp crown facets; abraded pavilion.



Late 20th century ring: pavilion facets are a mess.

[allen]

Maybe something to do with the angles of the pavillion?

[Alan F.]

No arguing with those photos, and a classic illustration of "doubling".