Try Ammonium iron(III) sulfate, NH4Fe(SO4)2·12 H2O, also known as ferric ammonium sulfate (FAS) or iron alum. Highly soluble and less acidic than Aluminum sulfate.
Now in the presence of CaCl2. I think we get NH4Cl, CaSO4 and Fe(OH)3. Also, I like the idea of an ammonium salt with oil (also presence).