Copper RF build notes.
Copper is the most electrically conductive face in the catalogue, and the RF answer is the same disciplined one: shield, tune, test — the finished construction is proven on the target reader like every other build. What sets copper apart is its surface life. It oxidises faster than any other face in the range, so the protective clear route (or the decision to let it patina) is agreed on a physical sample, and dark marks with white QR panels carry the data reliably through that changing tone.