From Diablo Wiki
Topaz are one of the five types of gems found in Diablo III. The others are Amethyst, Emerald, Ruby, and Diamond, the last added in Patch 2.0.1 and Reaper of Souls. See the main gems article for full details about gem scarcity, upgrade recipes, strategy, and more.
The Topaz has generally been the least popular gem, with the Thorns build far from viable at any time prior to Reaper of Souls. Magic Find from the helm had some popularity, and Wizards and Witch Doctors enjoyed topaz in their armor, though more in Softcore than Hardcore.
Topaz became more popular in Reaper of Souls with improvements to Thorns, as well as the greatly-increased mainstat bonuses from the higher level gems. With Flawless Royal gems yielding 280 to mainstat, Wiz/WD players found great damage benefit, plus INT's secondary property of adding 1 point of Resist All for every 10 points of INT gave high level Topaz a good defensive bonus as well, providing nearly half the value of a Diamond socketed in armor.
|Chipped Topaz||5% More Magic Find||+6 +Intelligence||Melee attackers take 2 damage per hit|
|Flawed Topaz||7% More Magic Find||+10 Intelligence||Melee attackers take 3 damage per hit|
|Topaz||9% More Magic Find||+14 Intelligence||Melee attackers take 6 damage per hit|
|Flawless Topaz||11% More Magic Find||+18 Intelligence||Melee attackers take 10 damage per hit|
|Perfect Topaz||13% More Magic Find||+22 Intelligence||Melee attackers take 15 damage per hit|
|Radiant Topaz||15% More Magic Find||+26 Intelligence||Melee attackers take 30 damage per hit|
|Square Topaz||17% More Magic Find||+30 Intelligence||Melee attackers take 50 damage per hit|
|Flawless Square Topaz||19% More Magic Find||+34 Intelligence||Melee attackers take 100 damage per hit|
|Perfect Square Topaz||21% More Magic Find||+38 Intelligence||Melee attackers take 200 damage per hit|
|Radiant Square Topaz||23% More Magic Find||+42 Intelligence||Melee attackers take 350 damage per hit|
|Star Topaz||25% More Magic Find||+46 Intelligence||Melee attackers take 600 damage per hit|
|Flawless Star Topaz||27% More Magic Find||+50 Intelligence||Melee attackers take 900 damage per hit|
|Perfect Star Topaz||29% More Magic Find||+54 Intelligence||Melee attackers take 1250 damage per hit|
|Radiant Star Topaz||31% More Magic Find||+58 Intelligence||Melee attackers take 1800 damage per hit|
|Marquise Topaz||33% More Magic Find||+62 Intelligence||Melee attackers take 2500 damage per hit|
|Imperial Topaz (RoS only)||+35% Increased Magic Find||+100 Intelligence||Melee attackers take 3100 damage per hit|
|Flawless Imperial Topaz (RoS only)||+37% Increased Magic Find||+160 Intelligence||Melee attackers take 3725 damage per hit|
|Royal Topaz (RoS only)||+39% Increased Magic Find||+220 Intelligence||Melee attackers take 4350 damage per hit|
|Flawless Royal Topaz (RoS only)||+41% Increased Magic Find||+280 Intelligence||Melee attackers take 4975 damage per hit|
Diablo 3 Development Changes
During the Diablo 3 Beta test, Topaz granted Gold Find instead of Magic Find (this bonus was eventually switched with Emeralds). Topaz were also set to boost Defense when socketed in "other" type of items. They grant +Intelligence from such sockets in the final game.
Diablo II Topaz Stats
Though, their stats are not the same as Topazs in Diablo III. Here are the stats for topazes in Diablo II: Lord of Destruction.
|Quality||Weapon||Helm or Armor||Shield||Clvl Req|
|Chipped||+1-8 Lightning Damage||+9% chance to find magical items||+12% Lightning Resistance||1|
|Flawed||+1-14 Lightning Damage||+13% chance to find magical items||+16% Lightning Resistance||5|
|Normal||+1-22 Lightning Damage||+16% chance to find magical items||+22% Lightning Resistance||12|
|Flawless||+1-30 Lightning Damage||+20% chance to find magical items||+28% Lightning Resistance||15|
|Perfect||+1-40 Lightning Damage||+24% chance to find magical items||+40% Lightning Resistance||18|
|Items of Diablo III  Item Basics Normal Items Crafting Legendary Armor I Legendary Armor II Legendary Weapons 1h Legendary Weapons 2h Item Sets|
|Item Basics||Item Affixes||Interface||Artisans||Miscellaneous |
• Prefixes & Suffixes
|Diablo 3 and Reaper of Souls Item Sets||Reaper of Souls only |
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Crafted Item Sets
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