Prince William's Engagement Ring Means He's in It to Win It

Cristen Conger

Kate, Wills and The Ring. (Samir Hussein/Getty Images)

Prior to popping the question, Prince William says he carried around Kate Middleton's engagement ring for weeks -- in his royal rucksack, no less -- while the couple vacationed in Africa. The Prince was probably sweating bullets every time he reached in that rucksack because if he misplaced the bauble, there'd be no replacing it. He surprised his princess-to-be with the same sapphire and diamond ring his father presented to Princess Di. Presumably, Wills didn't have to pay a penny for the ring, but it's estimated worth is somewhere around $265,000 (or 127,000 quid, as Wills ol' chap might say). Middleton can also breathe a major sigh of relief knowing that, according to Rutgers research, the ring's hefty price tag means the Prince is totally into her. Big time.

Throughout the history of marriage, cross-cultural customs have dictated an exchange of gifts (i.e., dowries) to symbolize the quality of the nuptial match. Men offering women engagement rings is a relatively new tradition, becoming the gold standard only in the past century with the modernization of marriage laws. In 2007, a pair of researchers from Rutgers surveyed men who had bought engagement rings on their own, without any financial assistance, to assess whether the cost of those carats correlates to how valuable a man deems a future wife. Brides as property! How romantic!

The study (via Psychology Today) did find a bit of good news for guys out there scraping together cash for an engagement ring. The men dropped an average $3,531.72 on a ring, roughly 7 percent of their annual income. So forget what you heard about the two-month salary minimum. That said, men who made more money spent more on the ring, and women with higher incomes also received bigger rocks since they were more likely to couple up with the wealthier beaus. Younger women also were given costlier rings than older women, which was attributed to sexual selection theory and the higher mate quality associated with a female's youth (read: baby makin').

The researchers concluded that "the cost of an engagement ring (a man) offers might give a woman valuable information about his willingness to commit to the relationship and invest in her and her offspring." Considering the monetary and sentimental worth of Princess Di's ring, Middleton (age 28) can rest assured that she fetched top mate quality ratings -- thank heavens. But by the Rutgers' rubric, that's nothing compared to Disney princess of yesteryear, Hillary Duff. The 22-year-old got a $1 million diamond engagement ring and a new Mercedes to seal the deal. Apparently, her mate quality is off the evolutionary charts.

Follow Cristen & Molly from Stuff Mom Never Told You on Twitter and Facebook.