Solarium Bars can be crafted with 2 Solarium Ore at a furnace. Solarium is generated in the player's world by breaking the Solarium Shrine with a Solarium Rod. In order to get to the Solarium Shrine room, you must defeat the Golem to get an item to teleport you to the "Hidden Temple". You will be teleported to a room with two chests. both chests containing some things Golem drops.