The element ID of the material from which this face is composed.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 17.0.0.0 (17.0.1090.0)
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 17.0.0.0 (17.0.1090.0)