We talked about Jay-Z's Pyrex Vision hoodie earlier today, but let's take a second right now to acknowledge the crazy five kilo gold chain he also wore to the So So Def 20th Anniversary party. When Kanye West wrote "Chain Heavy" this was definitely what he had in mind. Seriously, five kilos? This chain puts all other ones to shame.

It turns out said chain was designed by Gabriel Jacobs owner Rafaello & Co. Jacobs is New York native, by way of Russia, and a third generation jeweler. He, along with Rafael Aranbayev and Eric Aranbayev, started the company in 2009. His celebrity clientele started with Willis McGahee of the Denver Broncos and has since grown to include big names like the whole Dipset team, Cee-Lo, Busta Rhymes, The-Dream, Lil Wayne, Carmelo Anthony, Nas, and Waka Flocka Flame (who once got 20 brick squad pieces done), to name a few. Of course Hov is a fan of Jacobs' work, too—he even gave Jacobs a signed Carter Brooklyn Nets jersey. When he's not making jewelry for celebs, he's also designing custom pieces for the Saudi royal family, who spent a couple of million dollars in one transaction (the biggest ever for Rafaello & Co.).

Click through the thumbs above for a closer look at Jay's chain, and watch the video below to learn more about Gabriel Jacobs.