the coal blocks can be used infinitly they wont go out in your furnace

Put the summary of the bug you're having here

What I expected to happen was that the coal block would be used up after a specific amount of blocks smelted
Describe what you thought should happen here

What actually happened was it isnt burning up i now smelted 10 stacks of sand with one block and it is still full with fire
Describe what happened here

Steps to Reproduce:
1. make a coal block
2. put it in your furnace
3. put what you want to smelt in the furnace
4. you have infinity fuel.