Saquon Barkley Turns Personal Logo Into 18-Karat Gold Pendant

Saquon Barkley loves his personal Nike logo so much, he decided to get the thing decked out in a brand new baller chain ... and man, does this thing shine!!!

TMZ Sports has learned ... the New York Giants superstar running back wanted to treat himself before the start of the new season ... so he hit up his go-to guy, celeb jeweler Leo Frost, to whip up a diamond copy of his signature bolt emblem.

We're told the piece is made up of 18-karat white gold and VVS diamonds ... which means it's super high quality.

Of course, you've seen Frost's work in the past -- dude's done awesome chains for Joe Burrow, Henry Ruggs, Justin Jefferson, Errol Spence, Jr. and more.