Terraria like game with tilemaps?

So I want to create a Terraria-esque game using tilemaps. I have the breaking and placing of blocks working great. But there is an issue, I want to make different tiles take a certain amount of time to mine. You can't set certain tiles to have specific variables like that. What do I do?

You can add an array the same size as your tilemap and store the values for each tile there. If you only need 1 value (mining time remaining), you can use 2D array. For multiple values use 3D array.