Natural Untreated Green Zircon 4.00 ct Oval and Diamond Halo Ring in 18kt White and Yellow Gold, SGL Report No. 200928B-SB

ARTICLE: Lady's ring, 18kt white and yellow gold, centering one natural, earth mined untreated green zircon within a diamond halo.

MOUNTING: Fabricated in 18kt white and yellow gold. Halo style head with diamond work continuing down the shoulders. Present finger size 6 1/4 US. Suitable for sizing.

CENTER STONE: One oval cut natural zircon weighing 4.00 carats, measuring 10.85 by 8.01 by 4.99 mm. Color described in the accompanying report as yellowish green.

REPORT: Accompanied by an SGL Gemstone Identification and Origin Report, report number 200928B-SB, dated September 29, 2020, signed by Bear Williams, FGA and Cara Williams, FGA. The report identifies the stone as zircon, variety green zircon, and states: natural, untreated.

ACCENT STONES: Round brilliant cut natural, earth mined diamonds, total weight approximately 1.00 carat, graded approximately G in color and SI1 in clarity.

CONDITION: Examined under magnification. All stones present and secure at the time of examination. Facet edges and junctions sharp with no abrasion. Mounting sound with no evidence of prior repair.

REMARKS: Two findings make this an unusual stone, and the report establishes both. It is untreated, which on a 4.00 carat zircon is uncommon. And the color is green, the scarcest natural color in the species and the one collectors pursue. Green arises through a process peculiar to zircon: the crystal incorporates trace uranium and thorium at formation, and over geological time the decay of those elements progressively disrupts the lattice, a condition known as metamictization. That structural change is what produces the color. It is therefore a record of the stone's age, formed in the ground over an immense span of time. Green zircon at this size with clean transparency is a collector's article.

NOTE ON RADIOACTIVITY: Because the question follows naturally from the above, it is addressed here directly. Zircon contains trace radioactive elements as a matter of course. The levels present in gem zircon are extremely low, the species has been cut and worn as a gemstone for well over two thousand years, and it is not regarded within the gem trade or by gemological authorities as presenting a health concern in normal wear.

CARE: Metamict zircon is structurally softer and more brittle than fully crystalline material, and zircon in general is prone to abrasion along facet edges. Clean with warm water, mild soap, and a soft brush. Keep away from ultrasonic machines, steam, and prolonged strong sunlight, protect from knocks, and store separately from harder stones.

Diamond weights and grades stated are approximate and determined while the stones are mounted. Center stone identification, weight, measurements, color description, and treatment are as stated in the accompanying report, which is furnished with the piece and governs in the event of any discrepancy.