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"Gruosi gets this molten color via a process called PVD (for physical
vaporization and deposition), during which rose gold is bombarded
electronically, which makes the metal change color and hold that
color deeply enough so that it will not scratch off."
Bill, Deborah & Michele
Reactive Metals Studio, Inc
928-634-3434, 800-876-3434, 928-634-6734fx