Minecraft PC Wiki

A diamond.

Diamonds, also known as Dias, are the second rarest and second most coveted items in Minecraft. They are considered mid to late game content. Diamonds can be used to make the second strongest tools and armor available in the game, with 1562 durability points. The term "diamond" refers to several blocks and items, a list of which is included below. 

List of diamond items and blocks

A Diamond Sword.