1860 Civil War period six pointed caltrop, anti horse spiked metal device thrown to the ground to impede cavalry. Each spike measure 1/2to an overall size about 1 1/2. Caltrops were small antipersonnel and anti-horse weapons with four sharpened spikes that would be scattered on roads, trails, or steam beds to puncture boots or hooves and disable the victim. These were designed with the four spikes so there was always one pointing up.
4 Types of Caltrop Spikes