Armor Properties (4e Variant Rule)
From D&D Wiki
Here are some new armor properties for use with 4e armor.
Fragile armors are constructed from materials inferior to iron, steel or bronze. They are developed by cultures who do not have access to such metals or have not had the inclination to mine and work with them. Example fragile materials are stone, bark, obsidian and bone. This property can also represent materials used for ceremonial purposes such as gold, silver or other soft metals.
When an critical hit is scored against your AC while you are wearing fragile armor, you can either accept the result or make the attacker reroll the attack. If you force a reroll, you must accept the new result and after the attack the armor breaks. Broken armor provides only half its normal AC bonus (rounded down) and looses its enhancement, properties and powers.
Broken armor can be repaired during an extended rest. It is assumed that you have the tools and skill required for this as part of your proficiency with the armor.
Example: Stone Lamellar Armor
- Bronze, Stone
Bronze or stone armor variants of heavy armor are treated as light armor for the purpose of resolving attacks that target the wearer. This renders the armor immune to the rusting attack of a rust monster, or the effects of a trap or dungeon feature that uses magnetism.
Example: Bronze Plate Mail