Matte black metal RF build notes.
The matte black face is a PVD or coated finish a few microns thick over steel — cosmetically decisive, electrically irrelevant. The RF build underneath is the same ferrite-shielded stack as any stainless card, so black programs choose freely across NFC tag phone-tap, standard HF, and high-security AES HF access routes. The coating earns its keep at marking: laser strips it back to bright steel, which is where black cards get their crispest contrast — proven, like the tap, on a finished sample.