Coin Caches are scattered throughout Rise of the Tomb Raider.
The Coin Caches are one of two hidden collectibles in Rise of the Tomb Raider, other being Survival Caches. Coin Caches however only give player the Byzantine Coins. They are indicated in the game with a slight glimmer on the ground. Reading Monoliths reveals the location of the coin caches on the map. Skills can be obtained to show their location with the Survival Instinct.