Ruby

Rubies are one of the four types of gems found in Diablo III.

Rubies are very useful socketed in weapons, especially since the Patch 1.0.7 buffed their damage. Prior to that patch Rubies were great in weapons for low and mid-level characters, since the damage added by the Ruby was very substantial. Rubies were not as useful for high level characters, since with better gear and increased Critical hit Chance stats, the Emerald with its Critical hit Damage bonus was much more powerful than the Ruby.

Rubies are coveted by Barbarians, since the +Strength bonus adds to their damage output.

Rubies are also very popular for the +%experience gain when socketed in helms. This bonus became much more popular after Patch 1.0.4 when the Paragon system was introduced and gaining experience from kills became a key preoccupation of level 60+ characters.

Development Changes

During development, Rubies added a bonus to the Attack stat, when socketed in "other" objects. This was changed to a +Strength bonus in the final game.

Ruby Stats

	Quality	Helm	Other	Weapon
	Chipped	Increases experience reward per kill by 5%	+6 Strength	+3 Minimum Damage, +3 Maximum Damage
	Flawed	Increases experience reward per kill by 7%	+10 Strength	+6 Minimum Damage, +6 Maximum Damage
	Regular	Increases experience reward per kill by 9%	+14 Strength	+9 Minimum Damage, +9 Maximum Damage
	Flawless	Increases experience reward per kill by 11%	+18 Strength	+12 Minimum Damage, +12 Maximum Damage
	Perfect	Increases experience reward per kill by 13%	+22 Strength	+15 Minimum Damage, +15 Maximum Damage
	Radiant	Increases experience reward per kill by 15%	+26 Strength	+18 Minimum Damage, +18 Maximum Damage
	Square	Increases experience reward per kill by 17%	+30 Strength	+21 Minimum Damage, +21 Maximum Damage
	Flawless Square	Increases experience reward per kill by 19%	+34 Strength	+25 Minimum Damage, +25 Maximum Damage
	Perfect Square	Increases experience reward per kill by 21%	+38 Strength	+30 Minimum Damage, +30 Maximum Damage
	Radiant Square	Increases experience reward per kill by 23%	+42 Strength	+40 Minimum Damage, +40 Maximum Damage
	Star	Increases experience reward per kill by 25%	+46 Strength	+60 Minimum Damage, +60 Maximum Damage
	Flawless Star	Increases experience reward per kill by 27%	+50 Strength	+80 Minimum Damage, +80 Maximum Damage
	Perfect Star	Increases experience reward per kill by 29%	+54 Strength	+100 Minimum Damage, +100 Maximum Damage
	Radiant Star	Increases experience reward per kill by 31%	+58 Strength	+120 Minimum Damage, +120 Maximum Damage
	Marquise Gem	Increases experience reward per kill by 32%	+62 Strength	+150 Minimum Damage, +150 Maximum Damage

Diablo II Ruby

Though Rubies were found in Diablo II, their stats are not the same as Rubies in Diablo III.

Quality	Weapon	Helm or Armor	Shield	Clvl Req
Chipped	+3-4 Fire Damage	+10 to Maximum Life	+12% fire resistance	1
Flawed	+5-8 to Fire Damage	+17 to Maximum Life	+16% to Fire Resistance	5
Normal	+8-12 to Fire Damage	+24 to Maximum Life	+22% fire resistance	12
Flawless	+10-16 to Fire Damage	+31 to Maximum Life	+28% fire resistance	15
Perfect	+15-20 Fire Damage	+38 to Maximum Life	+40% fire resistance	18

Patch 1.0.7 Buffs

The value of Rubies in weapons was considerably increased in Patch 1.0.7. Here's a quote from the patch notes:[1]

All ruby gems have had their weapon bonuses increased (these changes will apply to both existing rubies, as well as new rubies):

• Chipped Ruby: +3 minimum damage/+3 maximum damage (up from +2/+2)
• Flawed Ruby: +6 minimum damage/+6 maximum damage (up from +4/+4)
• Ruby: +9 minimum damage/+9 maximum damage (up from +8/+8)
• Flawless Ruby: +12 minimum damage/+12 maximum damage (up from +10/+10)
• Perfect Ruby: +15 minimum damage/+15 maximum damage (up from +11/+11)
• Radiant Ruby: +18 minimum damage/+18 maximum damage (up from +12/+12)
• Square Ruby: +21 minimum damage/+21 maximum damage (up from +13/+13)
• Flawless Square Ruby: +25 minimum damage/+25 maximum damage (up from +14/+14)
• Perfect Square Ruby: +30 minimum damage/+30 maximum damage (up from +15/+15)
• Radiant Square Ruby: +40 minimum damage/+40 maximum damage (up from +16/+16)
• Star Ruby: +60 minimum damage/+60 maximum damage (up from +17/+17)
• Flawless Star Ruby: +80 minimum damage/+80 maximum damage (up from +18/+18)
• Perfect Star Ruby: +100 minimum damage/+100 maximum damage (up from +19/+19)
• Radiant Star Ruby: +130 minimum damage/+130 maximum damage (up from +20/+20)
• Marquise Ruby: +160 Minimum and +160 Maximum Damage

These rubies have also had their bonus damage calculations changed, and will now add damage flatly to both the minimum and maximum values on weapons

For example, if you have a weapon that does 150-200 damage and you socket a Perfect Square Ruby (which adds +30 minimum damage/+30 maximum damage), your weapon will do 180-230 damage

The boosts to high end Ruby damage were enormous, and while Emeralds remain the weapon socket of choice for most characters, Rubies are useful for some classes and builds, especially those that deal damage with skill that do not or seldom proc their damage from critical hits.