This is a relatively common stone, but may vary a great deal in its characteristics, the green color generally being associated with the metamict state. Appearance The color varies from a slightly brownish green to brilliant rather cold green, or yellow green. Some examples are perfectly transparent; others can look cloudy and display close, parallel striations, which are the main signs of the breakdown of the crystal lattice. The luster is affected by this turbidity and is often much less strong than in other zircons. The same is true of the birefringene, which is obvious in the clearer, more lustrous green zircons, but hard to see in the others. The oval or round, mixed cut is the most common. The edges are easily damaged, especially those of the cloudier stones, which are not so hard.
Distinctive features Clear, lustrous stones still display some birefringence. In cloudy specimens, this is not visible, but the appearance and presence of striations are equally characteristic. In either case, it is fairly easy to distinguish green zircon from green sapphire, but rather harder to tell it from olivine and some green tourmalines. Green zjrcons with good luster and clearly visible birefringence (thus with high density and refractive indices) may display the physical properties of high zircon, but the density, refractive indices and birefringence are often lower. considerable variation being possible. Despite the metamict process, the absorption spectrum is usually quite distinctive.
Occurrence Most green zircons come from SriLankla Greenish to brownish-green specimens are also found in Burma.
Value Comparatively low, about the same as that of yellow zircon. Stones with inferior luster are even less valuable.
Simulants and synthetics Being of low value. lt has neither been imitated nor produced synthetically. -