This shoe is a new find for my collection. I believe it is a spare shoe used for emergencies.
The leather is in poor condition, but it is a boot that buckles over the hoof. It is very similar to a lawn boot, and can easily be mistaken for one at first glance, except that the lawn boots were made with a flat, solid surface of leather to prevent clumps of sod from being scooped out as the horse walked. This spare boot has a horseshoe attached to the bottom and is hollow with no bottom except for the shoe.
The spare shoe boot would probably have been carried along, perhaps in a carriage or wagon, in case a horse lost its shoe while working. It could easily be buckled in place so the horse would still be able to finish the day of work in comfort. Just like people, if you lost one of your shoes it would be difficult walking the rest of the day with one shoe missing.
In the middle of the toe area, the metal shoe is hinged to allow fitting on different sized hooves.
Overall it is a most interesting shoe!