Crystal Shard

Crystal Shards are a common Hardmode crafting material found in the Underground Hallow, where they grow on Pearlstone Blocks and Pink Ice Blocks, even when submerged in Water or Lava. They respawn randomly on Pearlstone and Pink Ice blocks in the Cavern layer and below, making farming possible. Crystal Shards are most easily harvested using a Pickaxe, but can also be freed by mining the blocks surrounding them. They emit a small amount of light, similar to Demonite Ore.

Crystal Shards are also placeable in nearly any position (on walls, floors, and ceilings) as background Furniture, though they are not nearly luminous enough to replace other light sources, and placement has no other functional effect. Although new Crystal Shards will only spawn on Pearlstone blocks in the Cavern layer, once harvested they can be placed anywhere.

Crafting all items, including only one color of Phasesaber, but excluding Crystal Bullets and Greater Healing Potions, requires 135 Crystal Shards. Add 250 to this number for one of each color Phasesaber.

Tips

 * Crystal Shards only appear in the cavern layer, and are an indication of actual Underground Hallow, as opposed to Hallow entities having strayed into other biomes.
 * Crystal Shards can be farmed by placing Pearlstone blocks in the Cavern Layer to create an artificial Underground Hallow. The area should be properly "insulated" using open areas, Clay Blocks, or Wood, three blocks wide, to prevent spreading of the Hallow.

Farming
By looking at the sell price and how easy obtaining crystal shards is, (if the player can handle the Underground Hallow enemies) one can see that they are a very good source of money, a max stack being worth more than. A Crystal Shard farm is one of the most efficient (if not the most efficient) ways to make money. To farm Crystal Shards, you will need to make a structure with the following pattern: a row of pearlstone horizontally (this can go on for an infinite number of blocks, depending on the size of the farm the player wants to build.) then a three block gap (tall enough for the player to stand in) and another row of pearlstone. Add more layers in this manner until the structure is a suitable size. Crystal Shards will spawn randomly on the pearlstone for the player to harvest with any pickaxe. (Weaker pickaxes are recommended so as to avoid breaking the pearlstone.)