Curb Bit
The bosses of this bit, made of gilded iron and copying early 17th-century Netherlandish bronze examples, are later additions. The rest of it is composed of probably genuine elements of an Italian bit made around 1560, the spikes attached to the shanks possibly being later additions as well.
The few representations of spiky shanks found in Renaissance bit books assign them different purposes, some stating that they ‘prevent the horse from catching the shanks and putting them in its mouth’, others that they are ‘war shanks for preventing catching them with the hand’. Yet, in any case, if the spikes are not mere forgery, they might simply had an ornamental purpose.