In a large saucepan cook shrimp in boiling water about 3 minutes or till shrimp turn pink; drain.
Rinse shrimp under cold water; drain well.
Drain pineapple chunks, reserving juice.
Combine pineapple chunks and orange sections; cover and chill.
For marinade, in a medium bowl combine 1/4 cup of the reserved pineapple juice, the mint, salt, and pepper.
Stir in cooked shrimp and the celery.
Cover and marinate in the refrigerator for 2 hours.
Drain off marinade; discard marinade.
Stir pineapple chunks and orange sections into shrimp mixture.
In a small bowl combine 2 tablespoons of the remaining pineapple juice and the yogurt.
Toss with the shrimp mixture.
Divide mixture among 4 small airtight containers.
Store up to 2 days in the refrigerator.