This ring bit is forged in iron, it has a high solid port,.
The port supports a ring that would pass around the horse's lower jaw to act as a curb.

The ring has nine rollers on it. The central roller is joined back to the cheeks by chains.

The short curved cheeks have separate loops for the headstall, and two sets of reins.

There is a solid curved band or pontezuela under the mouthpiece

The remarkable thing about the bit is the extensive inlaid decoration. There is thick silver coloured metal inlay in geometric patterns over most of the external parts of the bit, even the small rein rings, chains and rollers.

There are some losses to the inlay, particularly on the small rings and the pontezuela, please look at the images.
This style of decoration is characteristic of Chile and northern Argentina. It  probably dates from the late 19th or early 20th century.

Mouthpiece 9.8cm (4"), Ring 11cm (4½") x 12.5cm (5")
Weight 679g (1lb 8oz)