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Powers
Gems are tiny stones imbued with magical powers that can be used in socketed items. Each type of gem has different powers, and they have different effects based on what type of item they are socketed in. There are five grades to each gem type: chipped, flawed, normal, flawless, and perfect. The higher the grade, the more powerful the effect. You can socket the gem by picked it up and clicking on an item with empty sockets. The effects of gems are cumulative; three chipped sapphires in a bow will give you +3-9 cold damage (3 second duration). A socketed gem cannot be removed from its item, so choose wisely before placing that gem!
Transmuting gems
You can upgrade gems using the Horadric Cube. Place three gems of the same type and grade in the Cube and transmute. You will be left with one gem of the next higher grade. This can be useful to transform a lot of lower grade gems into a perfect.
Amethyst
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Amethyst |
+40 to Attack Rating |
+8 to Defense |
+3 to Strength |
 |
Flawed Amethyst
(Level 5) |
+60 to Attack Rating |
+12 to Defense |
+4 to Strength |
 |
Normal Amethyst
(Level 12) |
+80 to Attack Rating |
+18 to Defense |
+6 to Strength |
 |
Flawless Amethyst
(Level 15) |
+100 to Attack Rating |
+24 to Defense |
+8 to Strength |
 |
Perfect Amethyst
(Level 18) |
+150 to Attack Rating |
+30 to Defense |
+10 to Strength |
Sapphire
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Sapphire |
1-3 Cold Damage (1 Second Duration) |
+12% Cold Resistance |
+10 to Mana |
 |
Flawed Sapphire
(Level 5) |
3-5 Cold Damage (1.4 Second Duration) |
+16% Cold Resistance |
+17 to Mana |
 |
Normal Sapphire
(Level 12) |
4-7 Cold Damage (2 Second Duration) |
+22% Cold Resistance |
+24 to Mana |
 |
Flawless Sapphire
(Level 15) |
6-10 Cold Damage (2.4 Second Duration) |
+28% Cold Resistance |
+31 to Mana |
 |
Perfect Sapphire
(Level 18) |
10-14 Cold Damage (3 Second Duration) |
+40% Cold Resistance |
+38 to Mana |
Emerald
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Emerald |
+10 Poison Damage over 3 seconds |
+12% Poison Resistance |
+3 to Dexterity |
 |
Flawed Emerald
(Level 5) |
+20 Poison Damage over 4 Seconds |
+16% Poison Resistance |
+4 to Dexterity |
 |
Normal Emerald
(Level 12) |
+40 Poison Damage over 5 Seconds |
+22% Poison Resistance |
+6 to Dexterity |
 |
Flawless Emerald
(Level 15) |
+60 Poison Damage over 6 Seconds |
+28% Poison Resistance |
+8 to Dexterity |
 |
Perfect Emerald
(Level 18) |
+100 Poison Damage over 7 Seconds |
+40% Poison Resistance |
+10 to Dexterity |
Ruby
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Ruby |
+3-4 Fire Damage |
+12% Fire Resistance |
+10 to Life |
 |
Flawed Ruby
(Level 5) |
+5-8 Fire Damage |
+16% Fire Resistance |
+17 to Life |
 |
Normal Ruby
(Level 12) |
8-12 Fire Damage |
+22% Fire Resistance |
+24 to Life |
 |
Flawless Ruby
(Level 15) |
10-16 Fire Damage |
+28% Fire Resistance |
+31 to Life |
 |
Perfect Ruby
(Level 18) |
15-20 Fire Damage |
+40% Fire Resistance |
+38 to Life |
Topaz
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Topaz |
+1-8 Lightning Damage |
+12% Lightning Resistance |
+9% Chance to Find Magic Items |
 |
Flawed Topaz
(Level 5) |
+1-14 Lightning Damage |
+16% Lightning Resistance |
+13% Chance to Find Magic Items |
 |
Normal Topaz
(Level 12) |
+1-22 Lightning Damage |
+22% Lightning Resistance |
+16% Chance to Find Magic Items |
 |
Flawless Topaz
(Level 15) |
+1-30 Lightning Damage |
+28% Lightning Resistance |
+20% Chance to Find Magic Items |
 |
Perfect Topaz
(Level 18) |
+1-40 Lightning Damage |
+40% Lightning Resistance |
+24% Chance to Find Magic Items |
Diamond
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
|
|
Chipped diamond |
+28% Damage vs. Undead |
All Resistances +6% |
+20 to Attack Rating |
|
|
Flawed diamond
(Level 5) |
+34% Damage vs. Undead |
All Resistances +8% |
+40 to Attack Rating |
|
|
Normal diamond
(Level 12) |
+44% Damage vs. Undead |
All Resistances +11% |
+60 to Attack Rating |
|
|
Flawless diamond
(Level 15) |
+54% Damage vs. Undead |
All Resistances +14% |
+80 to Attack Rating |
|
|
Perfect diamond
(Level 18) |
+68% Damage vs. Undead |
All Resistances +19% |
+100 to Attack Rating |
Skull
| |
Gem Type |
Weapons |
Shields |
Helms and Armors |
 |
Chipped Skull |
2% Life Leech,1% Mana Leech |
Attacker Takes 4 Damage |
Regenerate Mana 8%, +2 Replenish Life |
 |
Flawed Skull
(Level 5) |
2% Life Leech, 2% Mana Leech |
Attacker Takes 8 Damage |
Regenerate Mana 8%, +3 Replenish Life |
 |
Normal Skull
(Level 12) |
3% Life Leech, 2% Mana Leech |
Attacker Takes 12 Damage |
Regenerate Mana 12%, +3 Replenish Life |
 |
Flawless Skull
(Level 15) |
3% Life Leech, 3% Mana Leech |
Attacker Takes 16 Damage |
Regenerate Mana 12%, +4 Replenish Life |
 |
Perfect Skull
(Level 18) |
4% Life Leech, 3% Mana Leech |
Attacker Takes 20 Damage |
Regenerate Mana 19%, +5 Replenish Life |