Alchemy - The home alchemist Tie

Alchemy is a pseudo science, where a person uses a variety of ingredients to create other things with them. Take something from pile A, and a bit from pile B and you get an apple in the end. Alchemists have been known to bring people back from the dead, however to make that happen, you need something of equal value, which would be another life, using that and the sorcerer's stone, they made it happen. But mostly alchemists are known for turning lead into gold, which they could do, but only under certain circumstances. The process has been lost to the ages, probably due to its use of unicorn blood, which is very hard to come by.