Hired Miner
Hired Miner50 GRAM in game (≈5,000 CROWN at the presale rate), 25 GRAM in the presale
A hired miner adds +45 base mining power on top of your drill and works next to it in the shaft. His power is multiplied by buildings, boosts and depth just like the drill. You can hire both miners, their power adds up.
Shards per hour from the miner = 45 × 300 × buildings × boosts × depth
At current competition that is about 291.72 CROWN per day.
Crown Miner