Tin Bar

A Tin Bar is a solid bar of tin metal crafted by Miners. It is used in the creation of Bronze Bars.

Source
This item is crafted by Miners with a skill level of 65. Smelting Tin stops giving skillups to Mining at 75.

The miner must be at a forge to smelt the ore into bars.

As an ingredient
The only known use for Tin Bars as an ingredient is in the production of Bronze Bars.

As a quest objective
During the Opening of the Gates of Ahn'Qiraj event Tin bars were required for the following quests as part of the war effort:
 * The Horde Needs Tin Bars!
 * The Horde Needs More Tin Bars!