A Yellow Stave, or power-rod, is of great value to all Mages. Each rod is about a foot long, and crafted from a smooth hard fired yellow clay. Each order has a certain stock of these staves which are given to trusted followers, and more are sometimes found in ancient ruins. They are almost never available for sale.
Yellow Staves can absorb fatigue that their wearers would otherwise take for casting a spell. The amount that a stave can absorb varies according to its quality, from 50 to 100. As the stave absorbs energy it grows gradually darker in colour, and fine cracks start to appear on its surface. When it has absorbed its final point of fatigue it shatters into yellow dust.
Recharging a stave is difficult, but not impossible. A sufficiently skilled potter (Craft / Pottery 4+) may fire a stave in a kiln at a temperature just high enough to vitrify the surface. For each full day of firing, the stave regains 1 point of capacity.