Polaris Laser Laminations can provide Franklin testing for your specific needs. Franklin testing consists of running a current through the metal to check its resistivity. As you may already know, copper is a good conductor. An uncoated lamination is also a good conductor.
Franklin testing provides general information about the chemical nature and use of the coatings. It also provides important data concerning limits to their use regarding: relative insulating ability, punchability, temperature stability, weldability, and fabricability.