This one’s mine, though I can and have made copies.
![Mixed metal curb chain bracelet](https://www.jhsilver.co.uk/blog/wp-content/uploads/2020/02/Img_2120s.jpg)
It consists of a sequence of silver, copper and brass links with a silver t-bar and loop clasp. Of course, yellow, red and white gold is another option, but may not have the claimed beneficial effect of copper.