Please note while my opinion is informed I am not staff, and anybody reading my comments should note that.
My opinion is that if an item incorperates the features of multiple items it will incorperate the cost of multiple items.
While experimenting if you try to make the item with less materials than that it will reduce your success rate.
The "field" for a ritual can be something other than a ritual cloth. I'd have to go digging to find where the ruling was posted, but I remember such options as "pacing the room" a placed rope or even a drawn circle in the ground. So far the only item that grants a bonus to casting and acts as a field is a ritual cloth. Most people tend to get used to the ritual cloth as being the only field used because it is used in conjucting with the healing spell.
Also remember that while the rulebook list the materials and skills required to make an item it does not list the manufacturing techniques, tolerences and all the nitty gritty details that an engineer,archmage,psiologist and the like can pour over to determine what the interactions of different properties of different items when combined.
Just think about putting multiple medicines together in one pill. It can be done with alot of research or recklessly with little research.
Let's use a battle capable iron ritual knife. The dagger/combat's design requiremnets aspect of the weapon is straigth forward it has to be durable enough to survive the stresses of combat & hold a viable edge. But the magical aspects have to be taken into account. What properties makes the iron ritual knife useful for taking down a ward? Is it the cold hammered iron that is the material that makes the blade that the magic resonates with? Is it the carefully etched runes and arcane sigils that do the effect? Other aspects?
Cold worked iron is supposed to be a bitch to make with a useful sharp edge in some stories. Etched runes and sigils could easily be damaged in battle & in some stories a one broken sigil can ruin the ritual the item is used with... and that is but a sampling of possible difficulties.
Ultimately I figure the techno-babble specifications on alot of these things are not going to be defined insted just keeping with the statistics already present and a simple random draw from a bag will be done to determine success of combining items via experiments.
-Mario-
-Starn-
"And they say my money can't protect me!" Starn says while putting on his silver helmet & loads his bone inlayed silver hand-cannon with golden bullets...
