There are several different currencies in Catalyst Black: Dust, Quint, Shards, and Marks.
Dust is earned from Ascension or by completing quests. Dust can be used to upgrade gear.
Quint is earned from opening Star and Astral Chests and is used to buy gear in the Quint Shop.
Shards come from playing matches or completing quests and can be used to unlock Chests.
Shards fill up the chest meter found in the quests menu. Once filled, a Moon, Star, or Astral Chest is unlocked — and the next random chest is waiting!
Marks are a premium currency. You can get them by purchasing them in the shop with real money or completing certain quests.
They can be used to buy Star and Astral Chests, and other items and packs from the shop such as Daily, Weekly, and Monthly rewards.