DaVinci's drawing of the helicopter, Tesla's designs for a death ray laser, etc. These are all a basis for Major Charges. The taboo for a lithomancer is at once simple and very complicated. Never build anything you draw. Once you actually start building, you lose all your charges.
Lithomancers make stuff and modify things.
A lithomancer can make something from nothing. A lithomancer can also change anything that someone built, making things bigger, stronger, tougher and more efficient. He also cannot break things or affect anything still alive. He could add a mechanical error to an engine, but couldn't ignite a gas tank. This won't immediately destroy the device, but can cause problems when the device is used i.e. a gun given a barrel too small for the type of bullets it uses will blow itself to hell when the trigger is pulled, but not until then.