Alex Cubed

Take your Minium Stone in the inventory or NEI, highlight it with your mouse, and press the uses key(I think by default it's U). It will show you all transmutations that the stone can do. M: Minium Stone G: Gold I: Iron Diamonds: M G _ G G _ G _ _ Gold: MI I I I I I I I Placing just a single diamond or gold with the mium stone will downgrade it back to gold or iron.