Diamonds

Diamonds were the premium currency of LEGO Minifigures Online. They could be found by smashing  Champions or enemies, completing missions, or buy purchasing them in the Shop/website.

Obtaining Diamonds through gameplay
Non members could obtain a very limited amount of Diamonds (<=10) every day by smashing enemies. For members, the daily limit was higher.

Buying Diamonds
The price in the Shop/Website
 * 1250 Diamonds - $4.99
 * 2750 Diamonds - $9.99
 * 9000 Diamonds - $29.99

Using Diamonds
Diamonds can be used to
 * Replay a dungeon that's in time-out for 25 Diamonds or less.
 * Revive a broken minifigure
 * Upgrade a minifigure (instead of with Stars) varies by level.
 * Buy a virtual Minifigure Bag (for online play only) for 1000 Diamonds.
 * Buy a Membership for 2000 Diamonds.

Trivia

 * Originally, Minifigures Online used Funcom Points instead of Diamonds. This was changed midway through Closed Beta.