“Rainbow Lattice” from Australia
These “rainbow lattice” specimens, a 4.14 g rough stone and a 2.18 ct kite-shaped cabochon, are from Harts Range in central Australia. Photo by Robert Weldon/GIA, courtesy of Rainbow Lattice.
One of the most striking materials encountered in the Riverpark Inn (Pueblo) Gem Show was “rainbow lattice.” This rare phenomenal gem is a variety of feldspar exhibiting aventurescence from exsolution hematite crystals and a rainbow lattice effect from oriented exsolution magnetite crystals. Supply is extremely limited, and the only source is the tiny Utnerrengatye mine in Harts Range, Northern Territory, Australia. Rainbow lattice was discovered in 1985 and acknowledged as a new gem material in 1989. One of the original discoverers, Darren Arthur, showed us all-new material he mined in 2018 and subsequently sorted and cut (see above). With its scarcity and unique appearance, rainbow lattice is a must for any serious rare gem collection.
