Final Fantasy VI copyright Square Enix.
Images used for educational purposes only.
Each Final Fantasy has its own system for levelling and learning new skills and abilities, and in Final Fantasy VI that system is governed by magicite. Found as glowing crystals a little ways into the game, magicite can be equipped by characters, thereafter accumulating AP. If a character accumulates enough AP with magicite attached they will gain new, permanent spells. Magicite may also bestow stat bonuses if equipped when a character gains a level, and they can be used as summons during a fight. In short, magicite is pretty damned versatile.

Below is a listing of the magicite in Final Fantasy VI. Included are their locations, when you can find them, how much it costs to summon their espers, the bonus gained to a character's stats upon level-up, which spells are learned by equipping the esper, and how many points you can towards learning a spell per AP gained after a successful battle.

Ramuh

Location: Zozo, World of Balance
Summon Cost: 25
Level Bonus: Stamina +1
Spells Taught / Learn Rate:
  • Thunder / x10
  • Poison / x5
  • Thundara / x2
Kirin

Location: Zozo, World of Balance
Summon Cost: 18
Level Bonus: None
Spells Taught / Learn Rate: 
  • Cure / x5
  • Libra / x5
  • Poisona / x4
  • Regen / x3
  • Cura / x1
Siren

Location: Zozo, World of Balance
Summon Cost: 16
Level Bonus: HP +10%
Spells Taught / Learn Rate:
  • Sleep / x10
  • Silence / x8
  • Slow / x7
  • Fire / x6
Cait Sith

Location: Zozo, World of Balance
Summon Cost: 28
Level Bonus: Magic +1
Spells Taught / Learn Rate:
  • Confuse / x7
  • Imp / x5
  • Float / x2
Ifrit

Location: Magitek Factory, World of Balance
Summon Cost: 26
Level Bonus: Strength +1
Spells Taught / Learn Rate:
  • Fire / x10
  • Fira / x5
  • Drain / x1
Shiva

Location: Magitek Factory, World of Balance
Summon Cost:
Level Bonus: None
Spells Taught / Learn Rate:
  • Blizzard / x10
  • Blizzara / x5
  • Rasp / x4
  • Osmose / x4
  • Cure / x3
Unicorn

Location: Magitek Research Facility, World of Balance
Summon Cost: 30
Level Bonus: None
Spells Taught / Learn Rate:
  • Cura / x4
  • Esuna / x3
  • Dispel / x2
  • Protect / x1
  • Shell / x1
Maduin

Location: Magitek Research Facility, World of Balance
Summon Cost: 44
Level Bonus: Magic +1
Spells Taught / Learn Rate:
  • Fira / x3
  • Blizzara / x3
  • Thundara / x3
Catoblepas

Location: Magitek Research Facility, World of Balance
Summon Cost: 45
Level Bonus: HP +10%
Spells Taught / Learn Rate:
  • Bio / x8
  • Break / x5
  • Death / x2
Phantom

Location: Magitek Research Facility, World of Balance
Summon Cost: 38
Level Bonus: MP +10%
Spells Taught / Learn Rate:
  • Berserk / x3
  • Vanish / x3
  • Gravity / x5
Carbuncle

Location: Magitek Research Facility, World of Balance
Summon Cost: 36
Level Bonus: None
Spells Taught / Learn Rate:
  • Reflect / x5
  • Haste / x3
  • Shell / x3
  • Protect / x2
  • Teleport / x2
Bismarck

Location: Magitek Research Facility, World of Balance
Summon Cost: 50
Level Bonus: Strength +2
Spells Taught / Learn Rate:
  • Fire / x20
  • Blizzard / x20
  • Thunder / x20
  • Raise / x2
Golem

Location: Jidoor Auction House, Both
Summon Cost: 33
Level Bonus: Stamina +2
Spells Taught / Learn Rate:
  • Protect / x5
  • Stop / x5
  • Cura / x5
Zona Seeker

Location: Jidoor Auction House, Both
Summon Cost: 30
Level Bonus: Magic +2
Spells Taught / Learn Rate: 
  • Rasp / x20
  • Osmose / x15
  • Shell / x5
Seraph

Location: Tzen, Both
Summon Cost: 40
Level Bonus: None
Spells Taught / Learn Rate: 
  • Raise / x5
  • Cura / x8
  • Cure / x20
  • Regen / x10
  • Esuna / x4
Quetzalli

Location: Solitary Island Beach, World of Ruin
Summon Cost: 40
Level Bonus: None
Spells Taught / Learn Rate:
  • Haste / x20
  • Slow / x20
  • Hastega / x2
  • Slowga / x2
  • Float / x5
Fenrir

Location: Mobliz, World of Ruin
Summon Cost: 70
Level Bonus: MP +30%
Spells Taught / Learn Rate:
  • Teleport / x10
  • Banish / x5
  • Stop / x3
Valigarmanda

Location: Narshe Cliffs, World of Ruin
Summon Cost: 68
Level Bonus: Magic +2
Spells Taught / Learn Rate:
  • Firaga / x1
  • Blizzaga / x1
  • Thundaga / x1
Midgardsormr

Location: Yeti’s Cave, World of Ruin
Summon Cost: 40
Level Bonus: HP +30%
Spells Taught / Learn Rate:
  • Quake / x3
  • Graviga / x1
  • Tornado / x1
Lakshmi

Location: Owzer’s Mansion, Jidoor, World of Ruin
Summon Cost: 74
Level Bonus: Stamina +2
Spells Taught / Learn Rate:
  • Cure / x25
  • Cura / x16
  • Curaga / x1
  • Regen / x20
  • Esuna / x20
Alexander

Location: Doma Castle, World of Ruin
Summon Cost: 90
Level Bonus: None
Spells Taught / Learn Rate:
  • Holy / x2
  • Shell / x10
  • Protect / x10
  • Dispel / x10
  • Esuna / x15
Phoenix

Location: Phoenix Cave, World of Ruin
Summon Cost: 110
Level Bonus: None
Spells Taught / Learn Rate:
  • Raise / x10
  • Arise / x2
  • Reraise / x1
  • Curaga / x2
  • Firaga / x3
Odin

Location: Ancient Castle, World of Ruin
Summon Cost: 70
Level Bonus: Speed +1
Spells Taught / Learn Rate: 
  • Meteor / x1
Bahamut

Location: Deathgaze battle, skies of the World of Ruin
Summon Cost: 86
Level Bonus: HP +50%
Spells Taught / Learn Rate:
  • Flare / x2
Ragnarok

Location: Narshe, World of Ruin
Summon Cost: 6
Level Bonus: None
Spells Taught / Learn Rate:
  • Ultima / x1
Crusader

Location: Defeat Eight Dragons, World of Ruin
Summon Cost: 96
Level Bonus: MP +50%
Spells Taught / Learn Rate: 
  • Meltdown / x1
  • Meteor / x10
Raiden

Location: Ancient Castle, World of Ruin
Summon Cost: 80
Level Bonus: Strength +2
Spells Taught / Learn Rate: 
  • Quick / x1
GBA and iOS Only

Leviathan

Location: Nikeah Ferry, World of Ruin
Summon Cost: 70
Level Bonus: Stamina +2
Spells Taught / Learn Rate: 
  • Flood / x2
Cactuar

Location: Desert west of Maranda, World of Ruin
Summon Cost: 50
Level Bonus: Speed +2
Spells Taught / Learn Rate: 
  • Teleport / x20
  • Vanish / x10
  • Hastega / x5
Gilgamesh

Location: Dragons’ Neck Coliseum, World of Ruin
Summon Cost: 99
Level Bonus: Strength +2
Spells Taught / Learn Rate:
  • Quick / x1
  • Valor / x5
Diabolos

Location: Dragons’ Den, World of Ruin
Summon Cost: 100
Level Bonus: HP +100%
Spells Taught / Learn Rate:
  • Graviga /x5
  • Gravija /x3