photo by Lyle Owerko, via DANNIJO

First came the Dens and Naveen's Gap billboard, then David Karp's Uniqlo ad, and now the photogenic founders of New York startups are showing in jewelry campaigns.

A new black-and-white series of portraits from DANNIJO, the social media savvy jewelry line, features both Foursquare's Naveen Selvaduari (well, his hand at least) and LearnVest's Alexa von Tobel, along with celebrities like Questlove.

DANNIJO's Facebook page has a link to its Foursquare's profile and we hear Ms. Von Tobel is longtime friend of DANNIJO co-founders, Danielle and Jodie Snyder. But this doesn't necessarily mean we'll be seeing Mr. Selvaduari in front of the camera more often.

"Did it as a favor to a friend, not connected to anything else...," he emailed Betabeat. "I'm amazed that you recognized my hand." Well, the Facebook tag did help. We're not that good.