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The Diablo 2 Wiki archive is available for anyone looking for information on Diablo 2. All information here is pre-D2R but contains a lot of useful information that is still relevant. Updated sections for new D2R features can be found on the PureDiablo Diablo 2 section

Amethyst

From Diablo 2 Wiki

Amethysts are gems found in Diablo II. Purple in color, Amethysts add strength, attack rating, and defense, depending on what type of item they are socketed into.

The most popular use is for the +strength granted by socketing them in helms and body armor.


Diablo III Amethysts

This gem type returns in Diablo III, but with very different bonuses.


Diablo II: Lord of Destruction

Like all gems, Amethyst stats were slightly improved in the expansion.

Quality Weapon Helm or Armor Shield Clvl Req
Chipped Amethyst-chipped.gif +40 to Attack Rating +3 to Strength +8 to Defense 1
Flawed Amethyst-flawed.gif +60 to Attack Rating +4 to Strength +12 to Defense 5
Normal Amethyst-normal.gif +80 to Attack Rating +6 to Strength +18 to Defense 12
Flawless Amethyst-flawless.gif +100 to Attack Rating +8 to Strength +24 to Defense 15
Perfect Amethyst-perfect.gif +150 to Attack Rating +10 to Strength +30 to Defense 18


Diablo II Classic Stats

Amethyst stats in D2C were slightly lower than they are in the expansion.


Amethyst

Quality Weapon Helm or Armor Shield Sell Price Clvl Req
Chipped Amethyst-chipped.gif +40 to Attack Rating +3 to Strength +5 to Defense 125 1
Flawed Amethyst-flawed.gif +60 to Attack Rating +4 to Strength +7 to Defense 375 5
Normal Amethyst-normal.gif +80 to Attack Rating +5 to Strength +9 to Defense 1250 12
Flawless Amethyst-flawless.gif +100 to Attack Rating +7 to Strength +12 to Defense 3750 15
Perfect Amethyst-perfect.gif +150 to Attack Rating +9 to Strength +16 to Defense 7500 18