Materials Assesment is a feature of a product.
Proper Materials Assesment is a prequisite for Life Cycle Assesment as in ISO 14000 for example. This is a very challenging question and requires professional researchers to tackle.
See w:Material Input Per Unit of Service for a concept for measuring use of materials in producing a service unit. It basically breaks products down to services and evaluates total displacement of materials such as water, air, ore, oil etc. for the whole Life Cycle of the product.
Please note: This is an important area of reasearch and all accumulated information should be recorded in Wikipedia since this is in no way a consumerium specific issue.