These copper items are from the brand Divine Copper, all items are made of 100% pure copper without blending or any other inner layers. That means that the content you put into them or water is always exposed only to pure coppper. We have ourselves visited the manucfacturing plant in Mathura, Northern India and seen their making. As they are handmade there can be some minor difference or mark on the product but we control them before sending them. But they are made by real artisans with pure copper.