Mary-Kate's Rock Cost More Than Tuition

Unless you live under a spectacularly large rock, you're probably heard that Mary-Kate Olsen is now engaged to Olivier Sarkozy. And speaking of large rocks...have you seen that ring? We have a lot of questions about that ring — did Mary-Kate purchase it herself? Who designed it? And, most importantly for us, what unusual object does it most resemble? Now we can rest easy, because the official details have been released.

Olsen's engagement ring is a vintage Cartier, purchased at a Sotheby's jewelry auction in NYC on February 6. According to StyleCaster, the circa 1953 ring was originally owned by a Tennessee jewelry collector and was estimated to go for between $40,000 and $60,000 at the auction. It was ultimately purchased for $81,250. This might sound like a horrifying sum of money for us little people, but compared to Kim Kardashian's $8 million dollar Lorraine Schwartz rock it's pretty much a steal.

While many of us might think the ring resembles the Eye of Sauron, vintage Cartier seems a fitting choice for Olsen, who has a well-known propensity for wearing unique vintage clothing. StyleCaster reports that the "center European-cut diamond clocks in at approximately four carats framed by 16 sapphires, and the petals are set with single-cut diamonds."

An unconventional engagement ring for an unconventional Olsen twin! No word yet on whether Olsen made the purchase herself, but no matter — the engagement is on and she has a ring to prove it.