Prince Albert Fiancée Charlene official portrait Wittstock engagement ring

Official portrait of Prince Albert, fiancée Charlene Wittstock, and, most importantly, close-up of her rock. Photo: Amedeo M. Turello, Monaco Palace / AP

There are certain things you expect from a princess-to-be: Fairy-tale beauty, flawless grooming, and a jewelry box fit for a royal.

From the looks of the engagement ring that HRH Prince Albert II of Monaco has slipped on the finger of his fiancée, South African beauty Charlene Wittstock, she's got all of those requisites covered.

The tiny Principality of Monaco released the couple's official engagement portrait and StyleList's eyes immediately darted to the blinding bling on Wittstock's manicured hand.

Her pear-shaped engagement ring, set in unique gray gold, is the "Tethys" design created by Parisian jeweler Maison Repossi. The sparkler's huge center stone is embellished with round diamond brilliants.

Diamond Information Center expert Francesca Ferrante tells StyleList: "The center stone looks to be about 3 carats and the estimated worth of the ring is at least $100,000. This is truly a regal and royal diamond that is fit for a princess."

Wittstock, a former champion swimmer who is 20 years younger than her prince, wore a seafoam green halter dress by Swiss designer Akris for the formal photo. The prince, 52, wore a dark suit, blue shirt, and patterned tie.

The groom-to-be told the newspaper Nice-Matin that the couple will wed next summer but did not offer a date.

If this impressive ring is any indication, expect nuptials befitting a monarchy marriage -- certainly not like the no-frills affair another May/September couple, Harrison Ford and Calista Flockhart, chose for their recent Santa Fe, NM, wedding.

Meanwhile, check out the details on recently engaged actress America Ferrera's ring.