How do you get legendary gems in Diablo 3?

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Tags

1. #amount
2. #legendary
3. #value
4. #after
5. #within
6. #completing
7. #urshi
8. #effect
9. #minutes
10. #players
11. #increases
12. #upgraded
13. #upgrade
14. #gains
15. #chances
16. #greater
17. #upgradeable