Gems (Japanese: ジェム, Jemu) are a type of equipment in Xenoblade Chronicles that provide a mechanical bonus of some sort, such as increasing Strength by 20, or resisting 50% of Spike Damage. Gems are activated by equipping them on Weapons or Armour which have gem slots. Many weapons and armour are available both with and without gem slots. Alternatively, some weapons and armour, called Unique items, have gems permanently attached to them.
Each piece of armour can hold up to one gem, and a weapon can hold up to three gems. Thus a character can equip up to eight gems. Some gems can only be equipped on one type of equipment - either weapons or armour, while others can be equipped on both weapons and armour.
- Main article: Gem Crafting
Gems can be crafted by combining Ether Crystals and/or Ether Cylinders in an Ether Furnace. Ether crystals are dropped by enemies, or collected through Mining. Mechon and other mechanical enemies drop ether cylinders instead of ether crystals.
When crafting a gem, two characters work together. One character serves as the Shooter and the other serves as the Engineer. Each character has different strengths and weaknesses in each role. If there is high party affinity, characters who are not crafting may also help, which can result in higher quality gems.
Each gem's page lists where to find gems and crystals. Additionally, mining locations are listed on each area's page and a complete list of all mining locations in Xenoblade Chronicles can be found on this page.
A gems's selling price depends on its rank and effects. The gem's effect tends to factor more prominently in its value than its rank. For instance, a Rank III Heat Sink gem is 4× as valuable than a Rank VI Agility Up gem, while a Rank VI Heat Sink gem is only 1.7× as valuable than a Rank III Heat Sink gem.
Farming gems to sell for gold is not a viable means of collecting gold quickly because of how this works. The more common types of gems that can be found early on in the game, as well as lower rank gems, will sell for negligible amounts of gold. The most valuable gem in the game which is not dropped by a superboss, Debuff Resist VI, sells for 6,875 G (8,250 G with Riki's Buy Stuff! skill), which is far more than most other rank VI gems but a lot less than many other late game materials and unique equipment. In general, selling excess equipment and materials throughout the game will net much more gold than selling gems.
The individual gem pages list the base value (sell price) of a Rank I gem. The values for higher ranks of gems are calculated as follows:
|1.2 × base value|
|1.5 × base value|
|1.8 × base value|
|2.0 × base value|
|2.5 × base value|
Gems are divided into types based on their mechanical effects. More details, including descriptions, stat breakdowns, and locations for all variations of a gem can be found on each gem's page.
Gems in this category increase a character's basic game statistics.
|Strength Up||Equipment||150||Increases Strength.|
|Agility Up||Equipment||50||Increases Agility.|
|Ether Up||Equipment||150||Increases Ether.|
|Muscle Up||Equipment||100||Increases Physical Defence.|
|Ether Def Up||Equipment||100||Increases Ether Defence.|
|HP Up||Equipment||50%||Increases max HP.|
|Critical Up||Weapon||25%||Increases Critical Hit Rate.|
|Attack Stability||Weapon||50%||Increases Weapon Minimum Attack Damage.|
|Attack Plus||Weapon||50%||Increases Weapon Maximum Attack Damage.|
Gems in this category modify attacks in some way. This category also includes Gems that debuff enemies.
|Electric Plus||Weapon||100%||Increases electric damage.|
|Double Attack||Weapon||50%||Grants a chance to attack twice when auto-attacking.|
|Spike||Armour||250||Deals spike damage to enemies when attacked.|
|Bleed Attack||Weapon||250||Adds Bleed effect to attacks.|
|Blaze Attack||Weapon||400||Increases chance of auto-attack dealing extra Blaze damage.|
|Chill Attack||Weapon||300||Increases chance of auto-attacks dealing extra Chill damage.|
|Poison Attack||Weapon||500||Increases chance of auto-attacks dealing extra Poison damage.|
|Lightning Attack||Weapon||500||Deals electric damage when auto-attacking.|
|Daze Up||Weapon||100%||Increases damage to Dazed enemies.|
|Topple Up||Weapon||100%||Increases damage on Toppled enemies.|
|Bleed Plus||Weapon||100%||Increases Bleed damage.|
|Blaze Plus||Weapon||100%||Increases Blaze damage.|
|Chill Plus||Weapon||100%||Increases Chill damage.|
|Poison Plus||Weapon||100%||Increases Poison damage.|
|Strength Down||Weapon||25%||Grants a chance to lower enemy's Strength.|
|Agility Down||Weapon||25%||Raises chance of an auto-attack reducing enemy's Agility.|
|Ether Down||Weapon||25%||Raises chance of an auto-attack reducing enemy's Ether.|
|Slow||Weapon||25%||Raises chance of an auto-attack inflict Slow.|
|Bind||Weapon||25%||Raises chance of an auto-attack inflicting Bind.|
|HP Steal||Weapon||200||Raises the chance of an auto-attack recovering HP.|
|Paralysis||Weapon||25%||Raises chance of an auto-attack inflict Paralysis.|
|Break||Weapon||25%||Raises chance of an auto-attack inflict Break.|
|Phys Def Down||Weapon||25%||Raises chance of an auto-attack reducing enemy's Physical Defence.|
|Ether Def Down||Weapon||25%||Grants a chance of successful attacks reducing enemy's Ether Defence.|
|First Attack Plus||Weapon||150%||Increases damage on the first attack of combat.|
|Back Atk Plus||Weapon||100%||Increases damage from attacks behind enemies.|
Gems in this category modify a character's defences.
|Slow Resist||Armour||100%||Increases Slow resistance.|
|Bind Resist||Armour||100%||Increases Bind resistance.|
|Paralysis Resist||Armour||100%||Increases Paralysis resistance.|
|Sleep Resist||Armour||100%||Increases Sleep resistance.|
|Confuse Resist||Armour||100%||Increases Confuse resistance.|
|Arts Seal Resist||Armour||100%||Increases Arts Seal resistance.|
|Daze Resist||Armour||100%||Increases Daze resistance.|
|Topple Resist||Armour||100%||Increases Topple resistance.|
|Lock-On Resist||Armour||100%||Increases Lock-On resistance.|
|Pierce Resist||Armour||100%||Increases Pierce resistance.|
|Divine Protect||Armour||100%||Increases Instant Death resistance.|
|Debuff Resist||Armour||100%||Resistance against all status ailments, except Topple and Daze.|
|Good Footing||Armour||100%||Increases Blow-Down resistance.|
|Bleed Defence||Armour||100%||Reduces Bleed damage taken.|
|Blaze Defence||Armour||100%||Reduces Blaze damage taken.|
|Chill Defence||Armour||100%||Decreases Chill damage taken.|
|Poison Defence||Armour||100%||Reduces Poison damage taken.|
|Spike Defence||Armour||100%||Reduces Spike damage taken.|
|Physical Protect||Armour||50%|| Activated at the start of a battle.
Reduces physical damage.
|Ether Protect||Armour||50%|| Activated at the start of a battle.
Reduces ether damage.
|Auto-Atk Stealth||Weapon||50%||Reduces accumulated aggro from auto-attacks.|
|Arts Stealth||Weapon||50%||Reduces accumulated Aggro from using Arts.|
Gems in this category aid the character in ways not related to movement or dealing damage.
|Haste||Weapon||50%||Increases frequency of auto-attack.|
|Damage Heal||Armour||200||Chance to recover HP when attacked.|
|Recovery Up||Armour||50%||HP Recovery amount increased.|
|Aura Heal||Armour||150||HP is recovered every 2 seconds.|
|Arts Heal||Weapon||150||Using Arts recovers HP.|
|Unbeatable||Armour||50%||Raises the chance of surviving with 1 HP when Incapacitated.|
|Daze Plus||Weapon||100%||Increases duration of Daze.|
|Topple Plus||Weapon||100%||Extends Topple time.|
|Buff Time Plus||Armour||150%||Extends Buff time.|
|Debuff Plus||Weapon||150%||Extends gem Debuff time.|
|Weapon Power||Weapon||50%||Boosts activation rate for gems mounted on weapons.|
|Night Vision||Weapon||50%||Increases attack accuracy at night.|
|Initial Tension||Equipment||100%||Increases starting battle tension.|
|Aggro Up||Weapon||50%||Increases Aggro in battle.|
|Aggro Down||Weapon||50%||Decreases Aggro in battle.|
|Tension Swing||Armour||50%||Makes Tension change more easily.|
|Daze Tension||Weapon||25||Tension is raised by attacking a Dazed enemy.|
|Revival HP Up||Equipment||30%||Increases amount of HP recovered when revived.|
|Talent Boost||Weapon||12||Increases Talent Gauge gain from auto-attacks, but halves damage.|
|Heat Sink||Weapon||75%||Reduces Ether Rifle overheating.|
Gems in this category mostly provide benefits that are useful outside of combat, or assist in avoiding detection by enemies.
|Quick Step||Armour||25%||Increases Movement Speed.|
|Earth Cloak||Equipment||60%||Decreases detection range of land-based enemies.|
|Aquatic Cloak||Equipment||60%||Decreases detection range of water-based enemies.|
|Aerial Cloak||Equipment||60%||Decreases detection range of flying enemies.|
|Auto-Heal Up||Armour||25%||Increases HP recovery speed outside of combat.|
|Fall Defence||Armour||75%||Reduces falling damage.|
|Terrain Defence||Armour||75%||Decreases damage from hazardous terrain, such as poisonous bogs.|
Gems in this category increase a character's rate of advancement.
|EXP Up||Equipment||200%||Increases EXP gained.|
|AP Up||Equipment||200%||Increases Art Points gained.|