Cobalt Block

Beacon
Blocks of cobalt can be used to "power" a beacon. The beacon can be powered by a 3×3 square of cobalt blocks underneath it, and can optionally also include a 5×5, 7×7 and 9×9 layer in the shape of a pyramid under the original layer to increase the effects from the beacon.

Crafting
There is no usage of cobalt blocks. Just store useless Cobalt Ingot.