The server contains the following gems:

Small gems:

Where to get: in almost all dungeons.
Shining Gem - +8 defense (Inserted into shields, armor, tattoos)
Explosive Gem - +15 attack (inserted into gun)
Shadow Gem - +5 dodge (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff, boots)
Lustrious Gem - +5 hit rate (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff, gloves) 
Fiery Gem - +10 attack (inserted into one-handed swords)
Glowing Gem - +150 HP (inserted into shields, armor, tattoos)
Spirit Gem - +1 spr (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff, boots and rings)
Furious Gem - +13 attack (inserted into two-handed swords, bows, blades of voyager, staff)

Black Dragon Gems:

Where to get: the main way of prey is to kill the black dragon monsters.
Heart of Black Dragon - +500 HP (inserted into gloves and boots)
Soul of Black Dragon - +2 to physical resistance (inserted into shields, armor and tattoos)
Eye of Black Dragon - +65 attack (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)
Mind of Black Dragon - +500 SP (inserted into gloves and boots)

Jade:

Where to get: kill the mini-boss: Swamp Master (Dark Swamp - level 1).
You can also exchange 8 Coin of Chaos, which are obtained in the Silver Chaos from chests, for 1 specific gem at the NPC Chaos Administrator (234, 94).
Yellow Jade - +10 defense (inserted into hats)
Green Jade - +200 SP (inserted into hats)
Red Jade - +200 HP (inserted into hats)

New generation gems:

Where to get: all but Chiatan's Aura fall out of a Novice SW Chest in a Snow War. 
A random gem chest drops from the mini-boss: Swamp Champion, which is located in the Dark Swamp on the 2 level.
You can also exchange 8 Coin of Chaos, which are obtained in the Silver Chaos from chests, for 1 Chiatan's Aura at the NPC Chaos Administrator (234, 94).
Feng's Defense - +15 defense (inserted into shields, armor and tattoos)
Bing's Dodging - +10 dodge (inserted into boots)
Lock's Hit - +10 hit rate (inserted into gloves)
Shark's Strengthening - +300 HP (inserted into armor, shields and tattoos)
Chiatan's Aura - +10 crit rate (inserted into hats)

Broken Gems:

Where to get: they can be obtained using the item Gem Chest +2 which can be knocked out of ordinary monsters in a Forsaken City.
Broken Gem of the Wind - +2 agility (inserted into boots and rings)
Broken Gem of Striking +2 accuracy (inserted into gloves, bow, gun and rings)
Broken Gem of Soul - +2 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff and rings)
Broken Gem of Colossus +2 constitution (inserted into shields, armor, tattoos and rings)
Broken Gem of Rage - +2 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff and rings)

Cracked Gems: 

Where to get: they can be obtained using the item Gem Chest +3 which can be obtained by killing mini bosses of the 1st level of the Forsaken City, Abandoned Chest 1 and 2. As well as Obscure Chest 1 in the Dark Swamp.
Cracked Gem of the Wind - +3 agility (inserted into boots)
Cracked Gem of Striking - +3 accuracy (inserted into gloves)
Cracked Gem of Soul - +3 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)
Cracked Gem of Colossus - +3 constitution (inserted into shields, armor and tattoos)
Cracked Gem of Rage - +3 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)

Chipped Gems:

Where to get: сan be obtained by killing a Standard SW Chest in a Snow War.
Сan be obtained using the item Gem Chest +3 which is obtained from monsters: Abandoned Chest 3 (Forsaken City - 3), mini-boss: Master Swamp Watcher (Dark Swamp - 3), Obscure Chest 2 (Dark Swamp - 2), Obscure Chest 3 (Dark Swamp - 3).
Chipped Gem of the Wind - +4 agility (inserted into boots)
Chipped Gem of Soul - +4 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)
Chipped Gem of Striking - +4 accuracy (inserted into gloves)
Chipped Gem of Colossus - +4 constitution (inserted into shields, armor and tattoos)
Chipped Gem of Rage - +4 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)

Base Gems:

Where to get: you can get a random gem by killing a Expert SW Chest in a Snow War (SW). 
You can get a certain gem by killing a chest in Silver Chaos (SC). You can get a random gem by opening Gem Chest +5 which can be obtained by killing: Lost Pedestal (FC), Death Knight (FC), Pillar of Swamp (DS), Huge Mud Monster (DS), black dragon monsters (SW and SC).
Gem of the Wind - +5 agility (inserted into boots)
Gem of Striking - +5 accuracy (inserted into gloves)
Gem of Soul - +5 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff, gloves)
Gem of Colossus - +5 constitution (inserted into shields, armor, tattoos)
Gem of Rage - +5 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)

Great Gems:

Where to get: you can get it by opening Gem Chest +6, which can be obtained by killing: Lord of Abyss - Hardin, Kraken, lack Jewel, Prehistoric Giant Octopus, Barborosa, Deathsoul Commander.
You can also exchange 20-25 Coin of Snow War, which are mined in the Snow War from chests, for 1 specific gem at the NPC Administrator SNW (267, 93).
Great Gem of Wind - +6 agility (inserted into boots)
Great Gem of Striking - +6 accuracy (inserted into gloves)
Great Gem of Soul - +6 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)
Great Gem of Colossus - +6 constitution (inserted into shields, armor and tattoos)
Great Gem of Rage - +6 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)

Azrael gems:

Where to get: these gems can only be obtained using the island of Aurora. Read about it in the Aurora manual in another section.
Azrael's Aggregation - +8 accuracy (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff and gloves)
Undead Azrael - +8 constitution (inserted into armor и tattoos)
Azrael's Light - +8 spirit (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff, armor and tattoos)
Azrael's Glare - +8 strength (inserted into swords, two-handed swords, bows, gun, blades of voyager, staff)
Azrael's Dance - +8 agility (inserted into boots)

Gems of the Dead:

Where to get: these gems can only be obtained in the abode of the fallen. Read about it in the manual of the abodeof the fallen (AF).
Evasion of Dead - +15 dodge (inserted into boots and gloves)
Speed of Dead - +15 attack speed (inserted into boots and gloves)
Hit of Dead - +15 hit rate (inserted into gloves and boots)
Attack of Dead - +75 attack (inserted into any weapon)
Moveing Dead - +10 move speed (inserted into boots)
Life of Dead - +600 HP (inserted into shields or armors)
Protecting of Dead - +25 defense (inserted into shields or armors)

Class Gems:

Where to get: these gems can be obtained by opening the Chest of class gems. This chest is extracted from monsters: Black Jewel, Prehistoric Giant Octopus, Deathsoul Gunboat, Deathsoul Speed Boat, Skeletar Pirate Ship. Almost all of these monsters live in the sea near the Naval Base. A ticket can be bought from a grocer in the city. A ship can be built in the city at the NPС at coordinates 322, 120.
Gem Seaman's - Coral Ray enhanced by 5% (inserted into necklace)
Gem Arrow - Dual Shot enhanced by 5% (inserted into necklace)
Gem of Mage - Spiritual Bolt enhanced by 5% (inserted into necklace)
Gem of Swordsman - Illusion Slash enhanced by 5% (inserted into necklace)

Phantom Gems:

Where to get: these gems can be obtained by killing special bosses - prophets. To summon these bosses you need to get a summon scroll. It can be exchanged for 5 Talon 500 Reputation at the NPC in the Dream Village at the coordinates (441, 600).
Great Gem of Fox - Recover HP +7 (inserted into necklace)
Great Gem of Goddess - Recover SP +7 (inserted into necklace)
Great Gem of Phantom - Attack speed +12 (inserted into necklace)
Great Gem of Hardin - Move speed + 15 (inserted into necklace