Tin ore is best farmed around the Ruins of Alterac in Hillsbrad Foothills. Just farm the mountains on the edge of the Ruins. If there are other miners, you can also mine around the edges of the zone.
Note: If you are farming during Winter’s Veil, the holiday event in Hillsbrad Foothills can become dicey unless you are max level, as many PVP’ers will camp the holiday boss
They are also plentiful in Ashenvale, Northern Stranglethorn and Stonetalon Mountains.
When you mine tin ore, you also have the chance to mine gems and stone:
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