Now head back to Port Sarim, and Thurgo will tell you that he needs two iron bars (which you have in your inventory along with your pickaxe) and a blurite ore. The blurite ore can be found nearby. Look for the red exclamation point to the north and slightly east of Thurgo’s hut. Enter the cave and be careful. Almost all the NPCs in the area are aggressive.

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Try to stick to the walls and sprint through the cave.
You will pass muggers, then pirates and then some goblins.
Use food and sprint away if you need to do so.
In between the cavern sections, you can usually find a space away from wandering NPCs that you can rest up and recover your health.
Soon, you will get to some caves that are covered in ice.
Level 53 and 57 Ice Giants and Ice Warriors will be roaming the area.
The blurite ore is in this room, and you can sneak along the walls to get it.
(I recommend going during active times.
Other players can often keep the high leveled NPCs occupied while you grab the ore.)
Time the patrol carefully and do your best to avoid the warriors and giants. They can do quite a bit of damage. Get your ore, and then head back into the corridor where you will be safe for a bit. Recover your sprinting action points here, and when you believe you are ready to head out, sprint back to the entrance.