Jamaal Charles -- Chief of Bling Flashes Stats ... in DIAMONDS!!

Jamaal Charles isn't just dominating fantasy football -- he's now a beast in the iced-out custom jewelry department too ... after dropping $200k on RIDICULOUS chains, pendants and watches.

The Chiefs stud rolled into King Johnny's Custom Jewelry in Houston last week to pick up his new bling ... designed by Ice Man Nick. Ice's brother Zo tells TMZ Sports ... Jamaal requested pieces no one else would have, and they delievered ... big time!

For instance ... JC got a chain made out of a half kilo of gold, covered with more than 100 carats worth of diamonds. The custom touch? How 'bout a giant "5.0" pendant to remind FF geeks everywhere Jamaal's averaged at least 5 yards per carry for the last 3 seasons! That alone set him back $100k.

Zo says Jamaal also got a 10 oz. platinum bar with diamonds -- and a diamond encrusted Rolex Yacht Master II.