What does the optimal protection Gain Factor of F = 0.9 imply?
It means that the total number of points of the current protection type, times 0.9, Protection * 0.9 should come out even. Or else, you will again be wasting resources. Info: Luckily most permanent protection minerals up the values by 10, so that *all* combinations, listed in the table above, will come out even! Important: A few minerals, like Ruby or Quartz Crystals, up the protection values by 15, and Dragon Scale by 25. These should be used in pairs, to come out even. Example: You have 3 Ruby (Fire+15) and 7 Magnesite (Lightning+10) minerals, since you should use 15-up minerals in pairs this allows for this optimal combination: 2 x Ruby + 6 x Magnesite + 1 x Small Mana Potion (F = ((2+6)+2+8)/20 = 0.9). The brewed potion will then yield 27 Fire and 54 Lightning protection. Save the left over minerals in another potion.