Ja Morant just had one of the best jewelry shopping sprees ever -- he copped a bunch of expensive diamonds ... and then shot tequila with Gunna!!!
The fun time all went down at the Icebox jewelry store in Atlanta last week ... when the NBA star came to the famous showroom to get some of his old pieces cleaned up and to shop for more.
TMZ Sports has learned ... as the 22-year-old was browsing items -- they brought out Don Julio 1942, and everyone had a shot.
Later, "Drip Too Hard" rapper Gunna entered the shop -- and he, too, got in on the drinking!
The interaction between the guys was awesome -- they chatted it up about jewelry and admired some of the pieces in the store.
Eventually, we're told Morant copped several items -- a 14MM Miami Cuban bracelet, three other diamond bracelets and two diamond rings.
He also got a leather Icebox travel case to carry all his new bling ... and we're told his overall shopping spree bill came out to over $55K!
No word on what Gunna got while he was there -- but, at the very least, he got a fun memory!