This page defines a group of items, Dragonstone Armor.
Dragonstone Armor is the result of combining a Diamond Helmet, Chestplate, Leggings, or Boots with a Dragonstone Scale and a Dragonstone Upgrade Smithing Template on a Smithing Table.
Dragonstone Armor has the same stats as Netherite Armor, but with their armor and armor toughness values boosted by 1 point (the Horse and Nautilus Armor's armor values are boosted by 28). Also, they are unbreakable, meaning they won't take durability damage.
Unlike Netherite, Dragonstone Armor is not resistant to lava or fire.
Each piece of Dragonstone Armor worn by a player or mob gives them a speed debuff (more for the better pieces of armor). This debuff stacks, so wearing too much Dragonstone Armor is not a good idea.
It's generally the best idea to not use more than 2 pieces of Dragonstone Armor, or to use things that buff your speed, like Sweet Berry Cookies or the Agility enchantment.