Brazilian Watermelon Tourmaline with Iris Effect
These 18 × 18 × 4 mm watermelon tourmaline slices (17.82 ct on the left and 17.17 ct on the right) display an exceptional iris effect. Photo by Jeffrey Scovil.
The watermelon tourmaline slices shown in the figure above are remarkable for their mesmerizing iris effect. Unearthed from the famed Cruzeiro mine in the Brazilian state of Minas Gerais more than seven years ago, they were precisely cut to unveil their rainbow spectrum. Each slice, measuring 18 × 18 × 4 mm, radiates an alluring interplay of colors attributed to the iris effect, a phenomenon created by subtle internal fractures within the gemstone. This rare flawlessly matched pair weighed 34.99 carats total, conjuring the enchantment of fiery Australian opals.
