Lodestone

A lodestone is a block that can be used to alter the point where compasses lead.

From block loot
Lodestone requires a pickaxe to be mined, in which case it drops itself. If mined without a pickaxe, then the mining is slower and it drops nothing.

Breaking
Lodestone requires a pickaxe to be mined, in which case it drops itself. If mined without a pickaxe, then the mining is slower and it drops nothing.

Lodestone Compass
a compass on a lodestone changes the compass to point to the lodestone. In addition, the compass uses the enchant and potion glint. If a lodestone is broken, then the compass starts spinning, similarly to compasses in the End or the Nether. This works in all dimensions. A compass will start spinning if it is set to a lodestone in a different dimension. If a lodestone is destroyed while a paired compass is in a chest, shulker box, barrel, furnace, blast furnace, smoker, item frame, armor stand, or any other storage, the compass will not register that the lodestone is destroyed until the item is retrieved. However, placing a lodestone back in the exact position that the original lodestone was set while the compass is still in its container prevents the compass from spinning and unpairing once retrieved from its storage.

Trivia

 * In reality, [Wikipedia:Lodestone lodestone] is a naturally magnetized piece of the mineral magnetite, which can attract iron. They themselves are naturally occurring magnets.

Issues
Leitstein Magnetyt 磁石 Магнетит