copper }

copper is a chemical element (cu from latin cuprum) + atomic number 29, it's one of the few metals that occur in nature in directly usable metallic.

maintenance }

to keep your copper items beautiful, and your skin clear of possible irritation make sure to : always wear copper jewelry on top of your clothes. don't wear it directly on to your skin, make sure to sleep, shower, swim, perform household chores, sport without them. 

corrosion }

copper will eventually change from red to brown over time. if you don't like this antique patina for your item you could make it shiny + new again with a polishing cloth. a transparant anti tarnish coating can protect the metal and slow down the process. 

hardness }

3 on the scale of mohs, so glossy becomes a bit matte, matte becomes a bit glossy over time.