The metal is zinc alloy. Care instructions are enclosed in the box, but here is what you need to know.
You will receive your item in a sealed bag. As with most metals, humidity can occasionally affect the metal and it can darken a small bit. To clean the glass on your pendant wipe gently with glass cleaner sprayed on a cloth. Avoid allowing glass cleaner to touch the bronze too much.
We recommend avoiding spraying perfume on your piece or using lotion where it will come into contact. It's recommended that you occasionally polish your jewelry with a jewelry grade polishing cloth and rub a thin coat of olive oil to the back.
Brass can blacken when it is exposed to natural skin oils. You can avoid this by updated care.
Our real world 2-cents? Lisa and her mom have never once sealed the jewelry up in a bag, polished it, or done anything to care for it --and it still looks fabulous. We prefer low-maintenance jewelry that is ready-to-wear as we pull it from the jewelry box and wouldn't design anything else. But certainly follow our care instructions. 😉