Diamond randomly changes all affix values on the Items if the affix colors are:
Normal (Yellow), Epic (Orange), Legend (Red), and Crystal (Cyan).
Fluorite randomly changes the value of one affix of your choice if the affix colors are:
Normal (Yellow) and Epic (Orange).
Obsidian randomly changes the value of a Crystal affix on an Item:
these Crystals can’t be used on Eternal Items.
Crystal Emerald can increase an Items Item Quality to +25%, which increases your chances of getting maximum values.
on Legend Items, when changing affix values, values will not go below 75% of the affixes max value.
on non-Legend Items, changing affix values will give you random values between the affixes minimum and maximum values.
depending on what kind of affixes you have on your Item, you would use Diamond first, since it rerolls the values of all affixes at the same time. if you are trying to get max values on 2 or more Legend affixes, it might take lots of Diamonds, unless you get lucky. most players just get max value on one Legend affix. if one Legend affix can be rolled with Ruby, and the other is only found on Loot, max out the one that is Loot only, and then use Ruby to try to get the other one again with max value.
then use Obsidian to get max value on your Crystal affix, but you need to have only 5 affixes on the Item to do this, or it will not work. if you can, only take off an Epic affix or a Myth Stone if you don’t have an Epic, or a Legend affix that can be rolled with Ruby.
lastly, use Fluorite to max your Epic affixes. if you have Items with Normal (Yellow) affixes, and not enough Crystals to get Epic affixes, then you can max them also. Normal affix values are about 75% of Epic affixes.
only use Kyanite to take affixes off of an Item, as it will only take off the affix you chose. there are a few affixes it can’t take off, but still be careful, so you don’t take an affix off that you want to keep. Quartz takes off a random number of affixes, from 1 to 6, so only use it after you learn more about the game and understand how to properly use Quartz.