How to get the secret key - Roblox Refinery Caves
The key is needed to open a secret door in the mountains, top. After you open the door you must place a meteor in the bowl made for it. The meteor is sold for 55k in the farlands cave. After you place the meteor, a big one with very valuable ores inside will fall somewhere - Moonstone, Tolmedite and dumortierite if you get lucky (dumo is the best ore in the game).
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