At-will, standard action, touch, DC 19+; you transmute the material of an object you touch, changing one substance into another while retaining its current shape. Convert wood to stone, iron to gold, glass to steel, etc. The DC depends on how dissimilar the materials are:
Conversion
DC
Similar (oak to pine)
19
Related (wood to stone)
21
Different (iron to gold)
23
Exotic (lead to mithril)
25
The object can be up to 1 cubic foot at base DC; add +2 per doubling of volume.
The transmutation is permanent. Magical materials (adamantine, enchanted items) resist transmutation; add +4 DC.
You cannot create materials that don't exist or that you've never encountered.