Desert

The Desert is a sandy area that spawns desert monsters, cacti (as of Patch 1.05), and waterleaf. Each map will generally contain at least 2 desert areas. Drained Oceans also become deserts.

Making money
If a player is desperate for money, for example if they need to make a purchase but are somewhat short of Coins, deserts can be a good indirect source. Sand blocks can be used to craft Glass, which can then be used to craft Bottles that have a sell price of 4 Copper Coins each. Though the sell price is low, this is one of the only sources of coins in the game that is always readily available, as all other abundant block types have no value on their own.

Assuming the player carries only a Pickaxe and one other Weapon for fighting off any enemies encountered, while keeping all other inventory slots available for sand collection: 9,500 sand blocks (38 slots x 250 max sand stack per slot) = 4,750 Glass blocks = 9,500 Bottles x 4 Copper Coins each = 38,000 Copper Coins, or 3 Gold and 80 Silver Coins.