The Minecraft wiki tells us that Fortune applies to a certain set of blocks, but a person who I know and trust tells me that he has seen it work on iron ore, and gold ore blocks, which seems to contradict what I see in the wiki.
Can someone provide a more accurate source, perhaps the decompiled code or something giving a definitive answer as to exactly what the Fortune enchantment applies to?
Best Answer
Any block which drops an item other than the block itself when mined.
This includes:
Fortune works differently for different things. Most notably, at Fortune III you have a 20% chance to get twice as many drops, a 20% chance to get 3 times as many drops and a 20% chance to get 4 times as many drops for Coal, Diamond and Lapis Lazuli.
All others work similarly to Looting on a sword, increasing the maximum limit and therefore increasing the chance that it drops a lot of things, but not explicitly doubling or tripling the dropped amount.