http://www.polyvore.com/sphere_fish_tessellation_escher_ancient/thing?id=39634806

Gemini Sphere

Value: 100gp

Description: a strange light wooden sphere is carved from very soft wood. It constantly feels semi moist and when nocked sounds hollow.

The desert people of Agvex use plane spheres like this carved from a highly prized (and rare) tree cultivated by their people.

The wood actually allows water to be forced through with pressure but retains it until pressure is once again applied. This allows them to store water for long periods. The wood in combination with certain apparatus is also a prized method of water filtration.

This particular sphere must have been incredibly carefully crafted for a nobel or merchant as no noticeable seem can be found. It will fetch a good price to someone who has use for it or a noble but holds no overall value to common folks.