A Heart Crystal is a red heart-shaped stone that can be found underground. When used in a similar manner to Mana Crystals, it will permanently increase the player's health by 20, to a maximum of 400 health (can be taken to 500 health by obtaining Life Fruit, which are also found in the Underground Jungle). A Heart Crystal is only breakable with a Pickaxe or Drill. When broken, a Heart Crystal will drop one Life Crystal. It can be used to craft the
Heart Crystals cannot be obtained by breaking the blocks under them, and the two blocks it is on cannot be broken until the heart is gone.
The number of Heart Crystals in a world depends on the size of the world: there will be about 20-30 in small worlds, 30-35 in medium worlds, and 40-45 in large worlds.
When lava flows over one of these tiles, it will break and drop a Life Crystal.
These items are most common in the Underworld and Underground Jungle.
If a Heart Crystal spawns on sand or silt, then mining the sand/silt below it will cause it to float in midair.
It is possible to find a Heart Crystal standing on one tile.
Rarely, it may appear to overlap with other objects.
Sometimes, only half of a heart is visible.
The crystals were broken with a hammer before 1.2.
It is possible to spam Heart Crystals, Mana Crystals, potions, and boss summoning items on the Android version of Terraria. To do this, players can simply use the item and, right before it disappears, place it in their inventory.