Cobalt Ore
鏡鉄鉱 [kyoutekkou] or 'mirror-iron ore' in Japanese. 'Mirror-iron' is a name used for cobalt when it's written the Japanese way with kanji instead of a more western way with katakana.
Final Fantasy XIV

Use: Cobalt Ingot
Buy: - (sell: 126 gil)
Gather: mining (sweetspot -4, strike zone 5) Cedarwood, Iron Lake
Type: Ore, Stack: 99
Description: A decent-sized piece of rock containing the precious metal cobalt.
Pictlogica

Obtain: event quest FATE Joined
Use: required for EX Alchemy to create Cobalt Ingot
Type: Alchemy Material, Rarity: ★★★
Description: Material for EX Alchemy synthesization
Category: Item