Diamond

Diamonds are used to enchant level 65 endgame gear and various other pieces of gear.

Diamonds have various other uses like in server transfer where amount of gold you can take with you is limited. Or simply collecting them (especially before diamonds could be crafted and only rarely dropped as PVP rewards).

Crafting
This item can be acquired by crafting it using the Alchemy skill. Source material is Emeralds.

Price of Diamond Design in Alchemy shop is. Newer players might want to avoid buying this and instead buy Diamonds from Trade Broker if needed. Many older players have this design, as Diamonds were used to enchant level 65 endgame gear.

Drops
This item can be found by chance when opening:
 * Guardian Legion Jewel Box
 * Locked Strongbox
 * Locked Gem Strongbox
 * Various PVP event reward boxes

This item can be acquired by chance when completing any of these dungeons: (Diamond drop were removed from most of the dungeons. You now get equal price in Rubys.)
 * Gossamer Vault
 * Grotto of Lost Souls (7-Person)
 * Antaroth's Abyss (7-Person)
 * Dark Reach Citadel (7-Person)
 * Antaroth's Abyss (Hard)
 * Red Refuge (Hard)
 * RK-9 Kennel (Hard)
 * RK-9 Kennel
 * Ruinous Manor (Hard)
 * Antaroth's Abyss
 * Red Refuge
 * Thaumetal Refinery (Hard)
 * Sky Cruiser Endeavor
 * Ruinous Manor
 * Lilith's Keep (Hard)
 * Broken Prison
 * Ghillieglade
 * Pit of Petrax
 * Grotto of Lost Souls (Hard)
 * Grotto of Lost Souls
 * Dark Reach Citadel (Hard)
 * Dark Reach Citadel
 * Bahaar's Sanctum