Micah Parsons is so proud to be a Dallas Cowboy ... he just turned his #11 jersey into a diamond chain -- that's worth around $50k!!!
TMZ Sports has learned ... the 2021 NFL Defensive Rookie of the Year hit up Christian Johnston a while back to get some new America's Team bling.
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Johnston -- the founder of Shopgld -- says Parsons came through to his Miami store this week ... and he was very happy with what the jeweler churned out, calling the guy, "The G.