Dragon Scales and special drops
Farm White Titanite in Tomb of the Giants
Pinwheel Servants and Bone Towers provide repeatable chances at white upgrade materials for Divine and Occult weapons.
Tomb of the Giants, targeting Pinwheel Servants on the approach to Gravelord Nito and nearby Bone Towers.
The selected enemies respawn after resting, so the loop is repeatable. A slab is a very rare drop and cannot be expected each pass.
Stop when you have the chunks needed for the next upgrade step; continue the Pinwheel Servant loop only if the very rare slab is still worth pursuing.
Open a guide to find other locations and see what the item is used for.
Pinwheel Servants and Bone Towers provide repeatable chances at white upgrade materials for Divine and Occult weapons.