From Diablo Wiki
Star gems are the 11th rank of gem in Diablo 3 and Reaper of Souls. These gems never drop and can only be created by upgrading Perfect Square gems via the Jeweler. This was one of the most popular levels of gem for armor socketing in Diablo 3 vanilla, since it gave good stat upgrades over the lower level gems and wasn't too pricey to create.
With the closure of the Auction House and the advent of D3v2, players must find their own Flawless Squares to upgrade to higher level gems, rather than simply buying them in the Auction House. As each Star gem requires 27 Flawless Squares to upgrade, these gems can take some time to build up to.
- 3 Radiant Square gems (same type) + 20000 gold = 1 Star gem
- 3 Star gems (same type) + 30000 gold = 1 Flawless Star gem
A full list of gems by rank. Drop levels are approximate up to 60, with some overlap between each ascending level of gem.
- Chipped gem -- Drops from level 15-20 targets.
- Flawed gem -- Drops from level 21-25 targets. ]
- Regular gem -- Drops from level 26-30 targets.
- Flawless gem -- Drops from level 31-36 targets.
- Perfect gem -- Drops from level 37-42 targets.
- Radiant gem -- Drops from level 43-48 targets.
- Square gem -- Drops from level 49-54 targets.
- Flawless Square gem -- Drops from level 55-60 targets.
- Perfect Square gem -- Upgrade only.
- Radiant Square gem -- Upgrade only.
- Star gem -- Upgrade only.
- Flawless Star gem -- Upgrade only.
- Perfect Star gem -- Upgrade only.
- Radiant Star gem -- Upgrade only.
- Marquise gem -- Upgrade only in D3: Drops lvl 61+ in Reaper of Souls.)
- Imperial gem -- RoS-only. Upgrade, or rarely drops from lvl 61+ on Master+ difficulty.
- Flawless Imperial gem -- Upgrade only. RoS only.
- Royal gem -- Upgrade only. RoS only.
- Flawless Royal gem -- Upgrade only. RoS only.
Star Gem Stats
The stats for all types of Star Gems, as of D3v2 and RoS.
|Star Amethyst||+15% Life||+46 Vitality||Each Hit Adds +300Life|
|Star Diamond||Reduces cooldown of all skills by 8.5%||+46 Resistance to All Elements||Increases damage against Elites by 12%|
|Star Emerald||+25% Increased Gold Find||+46 Dexterity||Critical Hit Damage Increased by 70%|
|Star Ruby||Increases Bonus Experience by 25%||+46 Strength||+80 Damage|
|Star Topaz||25% Better Chance of Finding Magical Items||+46 Intelligence||Ranged and Melee attackers take 600 damage per hit.|
See the gems article for stats and upgrade costs for all ranks and types of gem.
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