Gem tag

All gems have gem tags (also called keywords) listed in the first line of the mouseover description. They are used for dividing the gems into groups and to clarify which type a skill/support is. They do not indicate which modifier (or stats) apply to a skill however.^[1]

Mechanics

Gem tags only group gem into categories, so specific effects like +x Level of Socketed <gem tag> Gems can apply to them, or interactions with specific subcategories of gems like Prismatic or Arcane.

Gem tags are properties of the gem item, and not properties of the skill(s) granted by the item, though typically at least one skill granted by a gem will have those properties. For example, the gem StormbindStormbindSpell, AoE, Channelling, Lightning, Duration, Arcane
Level: (1-20)
Cost: (3-5) Mana
Cast Time: 0.12 sec
Critical Strike Chance: 6.00%
Effectiveness of Added Damage: 160%Requires Level 28Channel to spread runes on the ground in a growing pattern. The runes fade away after a duration, or will be immediately removed and deal damage in a circular area when detonated by Rune Blast. Enemies standing on the runes are Hindered, reducing their movement speed.Deals (36-444) to (107-1332) Lightning Damage
Base duration is 12.00 seconds
50% reduced Movement Speed
Runes have 30% more Area of Effect per Improvement
Runes deal 100% more Damage with Hits and Ailments per Improvement
A Rune is Improved for each (5-24) Mana Spent
Runes can be improved 3 times

Additional Effects From 1-20% Quality:
Runes have +(0.5-10)% more Area of Effect per Improvement
(0.5-10)% increased Cast SpeedPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket. has the gem tag 'Arcane' and grants two skills: Stormbind itself, which is not arcane and can be supported by Archmage SupportArchmage SupportLightning, Arcane, Support, Spell
Icon: ^
Level: (1-20)Requires Level 31Supports spell skills that deal damage with hits and have no reservation. Cannot support arcane skills, Brand skills, Orb skills, Vaal skills, or skills used by totems, traps or mines. Cannot modify the skills of minions.Supported Skills gain Added Lightning Damage equal to (10-19)% of Unreserved Maximum Mana
Supported Skills have added Mana Cost equal to 5% of Unreserved Maximum Mana

Additional Effects From 1-20% Quality:
Supported Skills deal (0.5-10)% increased Spell DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket., and Rune Blast, which is arcane and therefore not supportable by Archmage.

In particular, there are common misconceptions about gem tags:

gem tags are only granted by gems; skills granted from items or threshold jewels do not modify gem tags in any way.^[2]
they cannot be added, changed, or removed.^[3]
they do not describe which skills can be supported by specific support gems and are not meant to, even if there is often overlap.^[2]
they do not describe which stats or modifiers apply to a gem.^[1]

Overview of gem tags

Category	Mainpage	Description
AoE	Area of effect	Skills that have some effects in an area of effect.
Arcane	Arcane	Skills which care about the amount of mana you have or spend for the purposes of that skill or support.
Attack	Attack	Skills that hit with unarmed or weapon damage.
Aura	Aura	Skills that grant or modify auras. An aura is an AOE buff that affects nearby allies or enemies. Many auras reserve a portion of the player's mana pool.
Blessing	Blessing skill	Blessing skill modify the reservation of the supported aura skill. Only one aura from a Blessing skill can be active at a time.
Blink	Blink	Travel skills that share a cooldown when used.
Bow	Bow	Attack skills which require a bow to be used. They implicitly also imply the projectile gem tag.
Brand	Brand	Spell skills that create magical brands, which attach themselves to an enemy for a duration and activate skills at fixed intervals. Brands count as dealing damage directly.
Chaining	Chaining	Skills that have the ability to chain by default. Applies to both projectiles and skills that emit chaining beams like ArcArcSpell, Chaining, Lightning Level: (1-20) Cost: (8-23) Mana Cast Time: 0.70 sec Critical Strike Chance: 6.00% Effectiveness of Added Damage: 120%Requires Level 12An arc of lightning reaches from the caster to a targeted enemy and chains to other enemies, but not immediately back. Each time the arc chains, it will also chain a secondary arc to another enemy that the main arc has not already hit, which cannot chain further.Deals (6-198) to (32-1122) Lightning Damage Chains +(4-7) Times 15% more Damage with Hits and Ailments for each remaining Chain Additional Effects From 1-20% Quality: Chains +(0.05-1) TimesPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket..
Channelling	Channelled skill	Skills which can be held down to be used continuously. Channelling skills often provide greater effects after being used for a certain duration.
Chaos	Chaos Damage	Chaos is one of the five damage types. Chaos damage cannot be reflected and ignores energy shield by default.
Cold	Cold Damage	Cold is one of the five damage types.
Critical	Critical strike	Skills which affect your critical strikes, or provide effects on critical strike.
Curse	Curse	These skills apply a special type of debuff to enemies. By default, you can only apply one curse per target unless you increase the curse limit.
Duration	Duration	Certain skills have an effect over time or activate after the duration. In some cases, such as curses, reusing the skill will reset the timer.
Exceptional	Exceptional support gem	Gem tag reserved for Empower SupportEmpower SupportExceptional, Support Icon: + Level: (1-3) Cost & Reservation Multiplier: 130%Supports any skill gem. Once this gem reaches level 2 or above, will raise the level of supported gems. Cannot support skills that don't come from gems.+(0-2) to Level of Supported Skill Gems Additional Effects From 1-20% Quality: This Gem gains (5-100)% increased ExperienceThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket., Enhance SupportEnhance SupportExceptional, Support Icon: + Level: (1-3) Cost & Reservation Multiplier: 120%Supports any skill gem. Once this gem reaches level 2 or above, will raise the quality of supported gems. Cannot support skills that don't come from gems.+(0-16)% to Quality of Supported Skill Gems Additional Effects From 1-20% Quality: This Gem gains (5-100)% increased ExperienceThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket., and Enlighten SupportEnlighten SupportExceptional, Support Icon: + Level: (1-3) Cost & Reservation Multiplier: (100-92)%Supports any skill gem. Once this gem reaches level 2 or above, will apply a cost & reservation multiplier to supported gems. Cannot support skills that don't come from gems. Additional Effects From 1-20% Quality: This Gem gains (5-100)% increased ExperienceThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket., as well as their awakened variants.
Fire	Fire Damage	Fire is one of the five damage types.
Golem	Golem	Golems are a type of minion that provide a buff to the summoner while active.
Guard	Guard Skill	Skills with defensive buffs. These all share the same cooldown.
Herald	Herald	Skills which reserve mana to provide a player with a permanent buff.
Hex	Hex	Skills that apply a type of temporary curse or interact with hexes. Hexes can be turned into auras or ground effects.
Lightning	Lightning Damage	Lightning is one of the five damage types.
Link	Link skill	Skills which target other players to apply buffs or trigger effects while linked. The link breaks if the target moves out of range or breaks line of sight. If the linked target dies, the user also dies.
Mark	Mark	Skills that apply a type of permanent curse. Only a single mark can affect a target at one time.
Melee	Melee	Skills which deal melee damage. Some melee skills require certain weapon types.
Mine	Mines	Skills which throw mines which need to be remotely detonated. Note that most spells or projectile attacks can be turned into a mine with the Blastchain Mine SupportBlastchain Mine SupportSupport, Mine Icon: Y Level: (1-20) Cost & Reservation Multiplier: 50%Requires Level 8Supports spells, or attacks that use bows or wands. Instead of using that skill, you will throw a mine that will use the skill for you when you detonate it. Mines cannot use channelling skills.Supported Attack Skills cannot be used with Melee Weapons Supported Skills deal (59-53)% less Damage Mine lasts 5 seconds Supported Skills have a Base Mine Detonation Time of 0.25 seconds Supported Skills gain a Base Reservation equal to Base Mana and Life Cost Supported Skills deal 5% more Damage for each prior Mine in Detonation Sequence Additional Effects From 1-20% Quality: (0.5-10)% increased Mine DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. or High-Impact Mine SupportHigh-Impact Mine SupportMine, Support, AoE, Aura Icon: Y Level: (1-20) Cost & Reservation Multiplier: 50%Requires Level 31Supports spells, or attacks that use bows or wands. Instead of using that skill, you will throw a mine that will use the skill for you when you detonate it. Mines cannot use channelling skills.Supported Attack Skills cannot be used with Melee Weapons Mine lasts 5 seconds Supported Skills gain a Base Reservation equal to Base Mana and Life Cost Supported Skills have a Base Mine Detonation Time of 0.25 seconds Supported Skills deal (56-50)% less Damage Each Mine from Supported Skills applies 2% chance to deal Double Damage to Hits against Enemies near it, up to a maximum of 100% Additional Effects From 1-20% Quality: (0.5-10)% increased Mine DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. support gems.
Minion	Minion	Skills let characters that create or affect minions.
Movement	Movement	Skills that affect movement speed or deals damage while moving.
Nova	Nova	Skills with an area of effect centered around the user.
Orb	Orb	Skills which last for duration and have a periodic effect in an area, and is not targetable by enemies.
Prismatic	Prismatic	Skills which pick a random element to attack with, avoiding choosing the same element twice in a row.
Projectile	Projectile	Skills that can create projectiles.
Physical	Physical damage	Physical damage is one of the five damage types.
Retaliation	Retaliation	Skills which become briefly Usable when a certain condition is met, namely blocking or taking damage. Retaliation skills can't be used until they become Usable, and have a cooldown once used.
Slam	Slam	Melee skills that hit the ground to deal area of effect damage.
Spell	Spells	Skills that do not scale with weapon damage.
Strike	Strike	Melee skills that hit one or more specific targets within melee strike range. Strike skills can be enhanced by increasing additional strike targets or supported by Melee Splash SupportMelee Splash SupportSupport, Melee, Attack, Strike, AoE Icon: S Level: (1-20) Cost & Reservation Multiplier: 130% AoE Radius: 14Requires Level 8Supports melee strike skills, causing their melee strike to deal splash damage around each target hit.Supported Skills deal Splash Damage to surrounding targets Supported Skills deal 40% less Splash Damage to surrounding targets Supported Skills have (0-57)% more Melee Splash Area of Effect Additional Effects From 1-20% Quality: Supported Skills have (0.5-10)% increased Area of EffectThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. to create AoE effect which can overlap multiple enemies.
Support	Support gem	Gems which support skills, enhancing or modifying their effects.
Stance	Stance	Skills that give the player a set of buffs that can be swapped between each other. Currently, Blood Stance and Sand Stance are the only Stances in the game.
Totem	Totem	Skills which place stationary totems to use various skills indirectly. Note that most spells and bow/wand attacks can be turned into a totem with the Spell Totem SupportSpell Totem SupportSupport, Spell, Totem Icon: T Level: (1-20) Cost & Reservation Multiplier: 200%Requires Level 8Supports spell skills that are not triggered. Instead of casting that spell, you will summon a totem that casts the spell for you.Supported Skills deal (49-40)% less Damage Supported Skills will summon a Totem which uses that Skill Totem lasts 8 seconds Supported Skills have 40% less Cast Speed Additional Effects From 1-20% Quality: Supported Skills have (0.5-10)% increased Totem Placement speedThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. or Ballista Totem SupportBallista Totem SupportBow, Projectile, Support, Totem Icon: R Level: (1-20) Cost & Reservation Multiplier: 120%Requires Level 8Supports any bow or wand attack skill, causing it to summon a ballista totem that uses the skill for you.Supported Attack Skills cannot be used with Melee Weapons Supported Skills deal (32-24)% less Damage Supported Skills will summon a Ballista Totem which uses that Skill Totem lasts 8 seconds Supported Skills have +2 to maximum number of Summoned Ballista Totems Supported Skills have 50% less Attack Speed Additional Effects From 1-20% Quality: Supported Skills have (0.5-10)% increased Totem Placement speedThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. support gems respectively.
Trap	Trap	Skills which throw a trap that triggers based on enemy proximity or after its duration expires. Note that most spells or projectile attacks can be turned into a trap with the Trap SupportTrap SupportSupport, Trap Icon: T Level: (1-20) Cost & Reservation Multiplier: 120%Requires Level 8Supports spells, or attacks that use bows or wands. Instead of using that skill, you will throw a trap that will use the skill for you when an enemy walks near it. Traps cannot use channelling skills.Supported Attack Skills cannot be used with Melee Weapons Trap lasts 4 seconds Supported Skills deal (20-6)% less Trap Damage Supported Skills have (0-19)% increased Trap Throwing Speed Additional Effects From 1-20% Quality: Supported Skills deal (0.5-10)% increased Trap DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket. support gem.
Travel	Travel	Skills that directly affect a player's position or phasing status.
Trigger	Trigger	Skills that cannot be used directly, and instead are used indirectly under specific conditions.
Vaal	Vaal skill	Skills need to be charged with Vaal Souls from kills or hits against rare or unique enemies in order to use them but are typically stronger or provide different effects than their base skill.
Warcry	Warcry	Warcries are skills that taunt nearby enemies and grant a warcry buff effect. Warcries typically gain Power that scales with the number and rarity of nearby enemies, which increases the buff's effects. Most warcries also cause your next few attacks to be exerted, giving them additional effects. Warcries are not considered spells or attacks and cannot be supported by trigger gems.

Modifiers that increase level of socketed gems based on gem tags

Name		Stats	Spawn Weighting
The Shaper's	80	+1 to Level of Socketed Skill Gems	body_armour_shaper 400
Warlord's	80	+1 to Level of Socketed Skill Gems	body_armour_adjudicator 250
Fletcher's	9	+1 to Level of Socketed Bow Gems	bow 1000
Sharpshooter's	64	+2 to Level of Socketed Bow Gems	bow 1000
Nihilist's	4	+1 to Level of Socketed Chaos Gems	attack_staff 1000 attack_dagger 1000
Anarchist's	55	+2 to Level of Socketed Chaos Gems	attack_staff 1000 attack_dagger 1000
Hunter's	68	+2 to Level of Socketed Chaos Gems	boots_basilisk 500
Frost Weaver's	2	+1 to Level of Socketed Cold Gems	attack_staff 1000 attack_dagger 1000
Winterbringer's	55	+2 to Level of Socketed Cold Gems	attack_staff 1000 attack_dagger 1000
Redeemer's	68	+2 to Level of Socketed Cold Gems	boots_eyrie 500
Flame Spinner's	2	+1 to Level of Socketed Fire Gems	attack_staff 1000 attack_dagger 1000
Lava Caller's	55	+2 to Level of Socketed Fire Gems	attack_staff 1000 attack_dagger 1000
Warlord's	68	+2 to Level of Socketed Fire Gems	boots_adjudicator 500
Thunder Lord's	2	+1 to Level of Socketed Lightning Gems	attack_staff 1000 attack_dagger 1000
Tempest King's	55	+2 to Level of Socketed Lightning Gems	attack_staff 1000 attack_dagger 1000
Crusader's	68	+2 to Level of Socketed Lightning Gems	boots_crusader 500
Combatant's	8	+1 to Level of Socketed Melee Gems	bow 0 wand 0 focus 0 shield 1000 weapon 1000
Weaponmaster's	63	+2 to Level of Socketed Melee Gems	bow 0 wand 0 focus 0 shield 1000 weapon 1000
The Elder's	80	+1 to Level of Socketed Support Gems	body_armour_elder 400
Redeemer's	80	+1 to Level of Socketed Support Gems	body_armour_eyrie 250
Subterranean	1	+2 to Level of Socketed Chaos Gems	abyss_jewel 0 jewel 0 boots 2000
Subterranean	1	+2 to Level of Socketed Cold Gems	abyss_jewel 0 jewel 0 boots 2000
Subterranean	1	+2 to Level of Socketed Fire Gems	abyss_jewel 0 jewel 0 boots 2000
Subterranean	1	+2 to Level of Socketed Lightning Gems	abyss_jewel 0 jewel 0 boots 2000
of the Underground	1	+1 to Level of Socketed Dexterity Gems	abyss_jewel 0 jewel 0 staff 750 sceptre 750 mace 750 axe 1000 sword 1000 bow 1600 dagger 1000 claw 1000 wand 750 str_armour 750 int_armour 750 dex_armour 1600 str_dex_armour 1000 str_int_armour 750 dex_int_armour 1000 str_dex_int_armour 1000 unset_ring 1000
of the Underground	1	+1 to Level of Socketed Intelligence Gems	abyss_jewel 0 jewel 0 staff 1000 sceptre 1000 mace 750 axe 750 sword 750 bow 750 dagger 1000 claw 1000 wand 1600 str_armour 750 int_armour 1600 dex_armour 750 str_dex_armour 750 str_int_armour 1000 dex_int_armour 1000 str_dex_int_armour 1000 unset_ring 1000
of the Underground	1	+1 to Level of Socketed Strength Gems	abyss_jewel 0 jewel 0 staff 1000 sceptre 1000 mace 1600 axe 1000 sword 1000 bow 750 dagger 750 claw 750 wand 750 str_armour 1600 int_armour 750 dex_armour 750 str_dex_armour 1000 str_int_armour 1000 dex_int_armour 750 str_dex_int_armour 1000 unset_ring 1000
Catarina's	60	+2 to Level of Socketed Support Gems +(5-8)% to Quality of Socketed Support Gems	weapon 2000 shield 2000
Chosen	60	+0.2 metres to Melee Strike Range +2 to Level of Socketed Melee Gems	helmet 1500 gloves 1500
Chosen	60	Projectiles Pierce an additional Target +2 to Level of Socketed Projectile Gems	helmet 1500 gloves 1500
Chosen	60	(8-10)% increased Area of Effect +2 to Level of Socketed AoE Gems	helmet 1500 gloves 1500

Version history

Version	Changes
3.25.0	Added Retaliation gem tag.
3.16.0	Added Critical gem tag.
3.15.0	Added Prismatic, Arcane gem tags.
3.13.0	Added Orb gem tags.
3.12.0	Added Hex and Mark gem tags.
3.11.0	Added Slam gem tag Added Stance gem tag. [Undocumented]
3.7.0	Added Physical, Guard, Strike, Blink gem tags.
Unknown	Introduced to the game.

References

↑ ^1.0 ^1.1 Mark_GGG (June 14, 2016). "Mechanical Questions Thread". Official Path of Exile Forums. Retrieved June 14, 2016.
↑ ^2.0 ^2.1 Mark_GGG (April 03, 2017). "Some Mechanics questions answered by Mark". Reddit. Retrieved April 03, 2017.
↑ https://www.reddit.com/r/pathofexile/comments/bv0j8g/questions_thread_may_31_2019/eq17dqx/?context=1

[ref1-1] 1.0 ^1.1 Mark_GGG (June 14, 2016). "Mechanical Questions Thread". Official Path of Exile Forums. Retrieved June 14, 2016.

[ref2-2] 2.0 ^2.1 Mark_GGG (April 03, 2017). "Some Mechanics questions answered by Mark". Reddit. Retrieved April 03, 2017.

[3] ttps://www.reddit.com/r/pathofexile/comments/bv0j8g/questions_thread_may_31_2019/eq17dqx/?context=1

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