The Mine unlocks at Level 8
A newer crafting building that was introduced in January 2015.
Black Stone: Tomatoes + Coins
Copper Ore: Milk + Coins
Diamond: Bamboo + Coins
Fossil: Linen Fiber + Coins
Iron Ore: Eggs + Coins
Long Bone: Broccoli + Coins
Magic Crystal: Fur + Coins
Quartz: Prickly pear + Coins
Soda: Wool + Coins
Stone of Unity is most often a Temporary craft:
Sunflower + Coins