JCK talks to retailers and designers about the most buzzed-about colored diamond engagement ring in years—and the effect it could have on the wedding jewelry market When Jennifer Lopez announced her engagement—or, more accurately, her reengagement—to Ben Affleck, the media frenzy surrounding her new ring came as no surprise. After all, this is J. Lo, the woman who launched a million search inquiries for pink diamonds, which she wore on her first go-round with Affleck. But the sparkler the multihyphenate talent now wears, an 8.5 ct. modified cushion-cut green diamond, might be more of a stretch for your everyday engagement ring shopper—at