I'm trying to determine how to get the date that a Potential/Deal was first saved in a given Stage. I had thought to create a separate formula field to capture the Stage that the Potential/Deal was last saved with, but I can't reference formula fields in formula fields.

I'm trying to do something like this

If ( OriginalStage != Stage && Stage = "Closed - Quote Submitted" )

      FirstSaved = Now

Else

      FirstSaved = FirstSaved

Is this sort of thing possible?