Marquise, baguette and old-cut diamonds, calibré-cut emeralds, onyx plaques, platinum and gold (security chain), circa 1925, signed B. S. & F.

Diamonds: marquise-shaped for an approximate weight of 1.20 - 1.40 carats; the remaining for an approximate total weight of 5.00 - 6.00 carats. Approximate total weight of 6.20 - 7.40 carats

Size/Dimensions: 18.4 cm long
Gross weight: 43.6 grams

Christie's, New York, December 2018, sale number 16332, lot 252

Founded in 1810 by Isaac Marquand as Marquand and Co., Black Starr & Frost holds the distinction of being the oldest jewellery firm in America. Marquand, an accomplished silversmith and clockmaker, initially sold a range of goods, including silverware, clocks and jewellery, from a small private office. Like many businesses of the time, it grew gradually, undergoing several name and location changes over the next few decades.
In 1833, Black Starr & Frost became the first to use plate-glass windows to display their merchandise, pioneering the popular New York City tradition of window shopping. It wasn’t until 1872 that the company adopted the name Black Starr & Frost, following the partnership of Cortland Starr and Aaron Frost.
In 1953, the brand was famously mentioned in Gentlemen Prefer Blondes, when Marilyn Monroe, playing Lorelei Lee, sang "Diamonds Are a Girl's Best Friend" and listed renowned jewellery houses: “Tiffany, Cartier, Black, Starr, Frost, Gorham, talk to me Harry Winston, tell me all about it.”
Black Starr & Frost also became the first luxury retailer on Fifth Avenue, today famously known as The Diamond District. In 1962, the company acquired the New York Cartier store, marking the beginning of its national expansion. In 2012, Black Starr & Frost sold the Archduke Joseph Diamond — a 76-carat, D-colour, internally flawless diamond, the largest ever to appear at auction — at Christie’s Geneva for $21.5 million, setting three world records for a colourless diamond.