Jasper52 to hold no-reserve auction of gemstones March 20

12.95-carat amethyst, Bolivia, VVS clarity, 18.48 x 12.50 x 9 mm. Estimate: $90-$120. Jasper52 image

NEW YORK – All colors of the spectrum are present in a loose gemstones auction to be conducted by Jasper52 on Tuesday, March 20. Absentee and Internet bidding is available through LiveAuctioneers.

This exclusive loose gemstones auction showcases a variety of cuts, stones and colors, from glowing green emeralds to deep purple amethysts. Bidders will find unique treasures in this 100-lot collection mined from around the globe.

Top-drawer examples start with Lot 1, a 12.95-carat oval amethyst (above) that is nearly three-quarter inches long (est. $90-$120.)

For sheer size, the auction features a 27.2-carat blue topaz (below), a cushion-cut gemstone that is nearly an inch long and one-half inch wide (est. $150-$200).

27.20-carat blue topaz, VVS clarity, Brazil, 22.5 x 12.6 x 11.15 mm. Estimate: $150-$200. Jasper52 image

Aquamarine, the March birthstone, is represented in seven of the auction’s lots. Among the nicest is a 5.07-carat stone that is more than a half-inch long in a rectangular step cut (est. $110-$125).

5.07-carat aquamarine, India, VS clarity, 16.9 x 7.2 x 5 mm. Estimate: $110-$125. Jasper52 image

The lone sapphire in the auction, an 18.74-carat pink star sapphire, has the auction’s highest estimate at $600-$700.

18.74-carat pink star sapphire, Burma, VVS clarity, 16.90 x 11.10 x 8.75 mm. Estimate: $600-$700. Jasper52 image

Kunzite is a relative newcomer to the array of colored stones available for use in jewelry, according to the GIA website (gia.edu). It is named after Tiffany & Co.’s mineralogist George Frederick Kunz, who was the first to identify it as a unique variety of spodumene in 1902. Kunzite gets its delicate color from trace amounts of manganese. Nine examples of kunzite are offered in the auction. The largest is a 13.57-carat pear-shaped stone that is more than a half-inch tall (est. 150-$175).

13.57-carat Kunzite, Afghanistan, VVS – IF clarity, 16.60 x 13.40 x 9.65 mm. Estimate: $150-$175. Jasper52 image

Tanzanite is the violet-blue to blue-violet variety of the mineral zoisite. It is mined commercially in only one area of the world: the Merelani Hills of Tanzania, which is where it gets its name. Five examples of Tanzanite are offered in several different shapes in the Jasper52 auction. The largest is a 2.16-carat tanzanite gemstone of the blue-violet variety in a rectangular cushion cut (est. $120-$150).