Wire wrapped, using copper wire. The gears are brass and copper. The chain is copper. I use copper because I like the fact that it darkens and can be antiqued. This necklace will tarnish as time goes by. You can clean your jewelry with a soft toothbrush using Twinkle or King Kleen copper cleaner. You may also use #0000 steel wool for surface cleaning. The darker pictures are more accurate. I made the images lighter so that you could see the detail better. The piece can be made more light copper with the above cleaners.