J.Lo's new emerald cut diamond looks to be about 15 carats, according to Alastair Smith, founder of Ringspo.com. Assuming A-Rod didn't skimp out when it comes to cut, color and clarity, Smith puts the cost of the ring at easily over $1 million.
But Lopez has been engaged a few times before and her rings have always been impressive.
Ben Affleck, for example, gave Lopez a $2.5 million, 6.1-carat pink diamond rock from Harry Winston. Smith points out that while Affleck's ring was lighter in carat weight, it was way more expensive because it used a rarer pink diamond.
Bennifer never made it down the aisle and J.Lo eventually gave back the ring.
Lopez was also famously married to Marc Anthony from 2004 until their divorce in 2014. For that marriage, the singer received an 8.5-carat blue cushion cut diamond which was estimated to cost $4 million.
J.Lo and A-Rod have been together for two years, and have basically been inseparable since first hooking up. They have showcased the blending of their families and past relationships, and pretty much been the romantic model of a perfect couple.