CalculationsbasedontheavailablethermodynamicdataofAuCl2^-andAu(HS)2^-indicatethatAuCl2^-isresponsibleforthetransportandenrichmentofgoldduringthestageofpre-concentrationinthesourcebedwhileAu(HS)2^-isthemaingoldspeciesinvolvedintheformationofgolddepositsinresponsetohydrothermalreworking.Acidchloridesolutionswithαcl^->10°andsulfur-richsolutionswitha∑sinexcessof10^-2areheldasimportantcriteriaforgoldenrichmentinthesourcebedandfortheformationofgolddepositsbysubsequenthydrothermalevent,respectively.