49ers' 'Game Changer' Chain Worth 6 Figures, Weighs 6.5 Pounds!

The iced-out playmaker chain Deebo Samuel rocked during "Monday Night Football" is as incredible as it looked ... 'cause TMZ Sports has learned the details behind the piece, and it came with a 6-figure price tag!!

The 49ers wide receiver donned the massive chain during the 4th quarter of San Francisco's 31-10 win over the L.A. Rams ... after scoring his second touchdown of the game.

The piece -- made by Rafaello and Co. in NYC -- had social media talking ... and now we have all the info behind the now-iconic chain.

We're told the "Game Changer" drip -- which was purchased by S.F. cornerback Jason Verrett -- is made of real, pure silver dipped in electro-plated yellow gold ... and is decked out in all-natural sapphires.

And, get this -- the whole thing weighs more than 6 1/2 pounds ... and took 9 weeks to complete.

We're told Rafaello and Co. is also behind another similar concept jewelry piece -- Manny Machado's "Swag Chain" he got for the San Diego Padres this past season.