Copper has an electromagnetic energy known as "prana shakti", which essentially means "life energy". This quality is the key reason why Ayurvedic medicine recommends storing water in a copper vessel.
When water is stored in a copper vessel, the "prana shakti" in the copper infuses and energizes the water. Copper infused water, which is known as "tamra jal", helps balance the three doshas and maintain a health pH balance in the body.
Meenakshi Gupta, a prominent Ayurvedic practitioner, wrote a very interesting article canvassing the reasons to try drinking water from a copper vessel. In that article, Ms. Gupta notes that the ancient practice is experiencing a modern reemergence:
"During my childhood days I remember my grandmother storing water in a copper vessel overnight and asking us to drink from it first thing in the morning. She claimed the water stored in a copper vessel was extremely healthy for the mind and body. Now when I see these ancient customs reemerging & my own findings with the healing ideologies of Ayurveda, I look back and think that I should have taken my grandmother’ s advice more seriously."
As Ms. Gupta writes, copper has amazing anti-microbial qualities, stimulates the brain, aids in weight loss, slows aging, and can even help fight cancer. It is so lovely to see ancient holistic practices reemerge!