Adrien Broner: Brace Yourself Normies ... My Bracelet Cost $750k

File this one under: Is it too late to become a boxer?

Adrien Broner doesn't have to ask that question ... 'cause the WBA lightweight champion is showing us all the upside of getting socked in the face for a living ... you can afford $750k jewelry for your trouble.

We spoke to Joe Avianne from Avianne & Co. jewelers in NYC and he told us Broner came to him wanting a 1-of-1 for his wrist ... basically something no one will ever have again.

Joe went to work for AB ... dreaming up a yellow stoned blinged out monstrosity with over 100 karats worth of diamonds in the bracelet that ended up setting the champ back 3 quarters of a mil.