[Chimera-users] placement of metal ion in the protein model

Good day to you, currently i am using Chimera to do some bioinformatics analysis, i want to put zinc ion into my predicted protein structure at the known binding sites, but i try to insert :Tools/structure editing/add ion/, but the option did not consists of zinc ion, hence may i know what are the alternative ways to introduce the zinc ion in order to facilitate the downstream application such as docking?? Hopefully can hear from you as soon as possible.... thank you -- Zhao Yang