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. They can grow in areas with or without Walls behind the initial Pearlstone or Pink Ice Blocks. They respawn randomly on Pearlstone and Pink Ice blocks in the Cavern layer and below, making farming possible. They emit a small glow, similar to Demonite Ore and Crimtane Ore.

On the Mobile and 3DS versions, Crystal Shards are pre-Hardmode, as they are dropped by Arch Demons (100% chance of 2-10 Crystal Shards).

Crystal Shards are also placeable in nearly any position (on walls, floors, and ceilings), 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. Crystal Shards will not spread Hallow.

Crafting all items, including only one color of Phasesaber (excluding consumables), requires a total of 115 Crystal Shards. Add 250 for all the other Phasesaber colors.

Tips

 * Crystal Shards have an unusually high sell value relative to their commonness, so farming them can be one of the most effective ways of making money throughout Hardmode. A full stack is worth.
 * Crafting and selling greater healing potions is more laborious, but yields even higher profits: Discounting the sale price of the pixie dust as well, this adds per crystal to the profit. A full stack of crystals (with a stack of sand and 30-odd stacks of pixie dust) would yield almost 100 stacks of potions selling for . The yield would be further increased by 50% (/crystal) if an Alchemy Table is used.
 * For farming, place single horizontal rows of Pearlstone, separated by three tile-wide gaps for walking and harvesting. The farm must be in the cavern layer or below. It may be worth sealing the farm using an outer frame of Clay Blocks or Wood followed by a three-block gap to prevent Hallow from spreading. Actuators can be used to switch Pearlstone to an inactive state, causing all Crystal Shards to drop for easy harvesting.
 * Crystal Shards emit a glow, so getting rid of light sources makes it much easier to spot them.

History
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