There are a lot of formulas for gold toners. Some have a short life even in glass bottles, while others have very long lives. I use thiocyanate toners, for which I have seven formulas, for salt and kallitype prints. My cost is very low and toning consistent because i use toners as single shot. I mix a liter of the two stock solutions of my favorite toner. 5 ml of each stock solution are diluted to a liter. I use 20 ml of this diluted toner for an 8x10 print and then discard it. Some papers soak up more of every solution than do others partly due to paper weight, and partly due to sizing.

A little research into gold toners will quickly reveal all of the formulas I have collected through research, and make obvious the one I prefer.