The ancient giants often fashioned wands, staffs, and other charged items from the branches of the eldritch whorlwood tree. When whorlwood is taken from a tree and fashioned into an object, the grain pattern in the wood is uncommonly twisted and gnarled. But as charges are expended and the magic gradually leaves a wand or staff made of eldritch whorlwood, the pattern of the grain gradually smoothes itself out. When the wand or staff is out of charges, the grain pattern is perfectly straight.
The ancient giants and learned spellcasters of today can examine the grain pattern in a whorlwood wand or staff and determine how many charges the item has left. Doing so requires a DC 15 Knowledge (arcana) check. The eldritch whorlwood tree thrives only when under magical care, so living examples are rare even in Xen’drik. Many wizard colleges and organizations such as the Twelve and the Arcane Congress would love to get whorlwood seeds or graftable branches of whorlwood so they could grow their own trees.
Eldritch whorlwood has hardness 6 and 10 hit points per inch of thickness. Wands and staffs made of eldritch whorlwood cost 5% more than versions made of normal materials.
Source: Explorer's Handbook