Have you bought the actual skill to make stone production? You can obtain the production skills for any of the productions anytime, but if have not selcted Stone making as your production, it will not let you use it.
I will try to find directions on how to select your productions.... it has been too long since I did it that I cannot remember exactly.
EDIT: Try this guide and see if it helps you. Let me know if you still have problems and I will see what I can do to help you further.
http://www.fiestafan.com/forums/show...ght=production