Look a little closer
A bag can combine fabric, a coated strap, metal hardware and a plastic closure. A single material word may conceal these differences. The components may also age or respond to handling differently, particularly in a historical collection.
A note for your design book
Draw a simple component map and record the declared material for each part where known. Identify the places where components meet without diagnosing their condition from appearance alone. Avoid choosing a cleaning treatment because it suits only the largest surface. For everyday products, use the maker’s care information; for historic mixed-material objects, appropriate conservation advice needs to consider the whole object.