Quantifying the release of base metals from source rocks for volcanogenic massive sulfide deposits: Effects of protolith composition and alteration mineralogy

► Protolith differentiation key in quantifying metal losses from sheeted dike complex ► Altering primitive protoliths gives high Cu + Ni: Zn + Mn fluids; evolved opposite ► All Cu and most Zn are leached from all rocks irrespective of alteration mineralogy. ► No Co and little Mn and Ni is lost during chlorite-amphibole alteration. ► Metal losses could have formed a large high grade Troodos VMS deposit.