Sapphire

Sapphire is a gem tradeskill material and is used by architects, armorers, and weaponsmiths.

Source
Sapphire is obtained through salvaging and from a Titanium Node or Zephyrite Node with the mining tradeskill and can be found in Auroria, Galeras, and Whitevale. This crystal can also be obtained from a Tier 1 or 2 Mineral Deposit.

Schematics
Sapphire is used in the following schematics: