Burns any wooden item?
The fuel list states that it will burn "any wooden item", but it will not burn Wooden Slabs. I suspect, but haven't tested, that it will not burn any wooden items that aren't burnable by the regular Furnace. --Trifler 07:19, 12 October 2011 (CEST)
Smelting rate and cost wrong
There seems to be a lot of conflicting information out there about smelting speed. This article says the iron furnace takes 8 seconds to smelt one item. The minecraft wiki entry for the stone furnace indicates it takes 9.25 seconds per operation but the table at the bottom of that page says it takes 10s per operation. I think the later is more likely, either way it's not 25% faster, it's more like 20%.