This is the most common form of scrying device, a crystal sphere about 6 inches in diameter.

A character can use the device to see over virtually any distance or into other planes of existence, as with the spell scrying (Will DC 16 negates).
Certain crystal balls have additional powers that can be used through the crystal ball on the target viewed. This one allows the use of detect thoughts (Will DC 13 negates).

Prerequisites: Craft Wondrous Item, scrying, detect thoughts.
Cost to Create: 25,500 gp, 2040 XP, 51 days.