I make these rings from round brass wire. To finish I mattify it and oxidize it, then i brush some of the oxide off, giving it a raw, rustic look.
They are made with 3mm (8g) wire and are available in two sizes: Small with inside diameter 40mm (approx. 1.5 inches) and Large with inside diameter 50mm (approx. 2 inches).
The small ones weigh 9.5 gram each and the large ones 11.5 gram each.
You can buy a single earweight or a pair.