The first room-temperature, vanishing-external-field kagome magnet discovered was the intermetallic Fe 3 Sn 2, as shown in 2011. Many others have since been found. Kagome magnets occur in a variety of crystal and magnetic structures, generally featuring a 3 d - transition-metal kagome lattice with in-plane period ~5.5 Å. Examples include antiferromagnet Mn 3 Sn, paramagnet CoSn, ferrimagnet TbMn 6 Sn 6, hard ferromagnet (and Weyl semimetal) Co 3 Sn 2 S 2, and soft ferromagnet Fe 3 Sn 2. Until 2019, all known kagome materials contained the heavy element tin, which has a strong spin–orbit coupling, but potential kagome materials under study (as of 2019) included magnetically doped Weyl-semimetal Co 2 MnGa, and the class AV 3 Sb 5 (A = Cs, Rb, K). Although most research on kagome magnets has been performed on Fe 3 Sn 2, it has since been discovered that FeSn in fact exhibits a structure much closer to the ideal kagome lattice.