By collecting Lucky Coins, you can exchange them for Lucky Ticket tickets and Jewel stones. To exchange Coin of Luck coins, you need to talk to NPC Delgado
Delgado exchanges Lucky Coin from x10, x20 to x30 pieces.
Lucky Coin coins can be stacked up to 255 pieces.

What can fall

Lucky Coin x10:

Misc: 1st Lucky Armor Ticket, 1st Lucky Pants Ticket, 1st Lucky Helm Ticket, 1st Lucky Gloves Ticket, 1st Lucky Boots Ticket

Lucky Coin x20:

Misc: 2st Lucky Armor Ticket, 2st Lucky Pants Ticket, 2st Lucky Helm Ticket, 2st Lucky Gloves Ticket, 2st Lucky Boots Ticket

Lucky Coin x30:

Jewel: Jewel of Extension, Jewel of Elevation