I have been mining rune ore and then buying coal ore in the GE for 45k ea. If you smelt them together you can make about 350k profit per bar with also getting pretty good xp.
The profit you make per hour depends on how AFK you are.
For me i was making an easy 350m an hour whilst watching suits season 4
If you push yourself to your maximum you can make 500m per hour
What it takes to make a rune bar:
1 rune ore
4 coal ore
What tools to use:
Best - Inferno adze
Next best - Sacred clay pickaxe
Minimum i would recommend - Dragon Pickaxe
Best place to do it:
Premium skilling zone is the best place
Crafting guild is also very good
Mining the rune ore:
Premium skilling zone
Mine the rune north of were you teleport to, there are two rune ores there
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Use the bank south of the rune ore.
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viewtopic.php?f=46&t=56590 - Great thread for location of rune ore - (i didn't make this thread)
You can mine the coal if you want:
Use the skilling teleport to get to the mining skilling zone
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Run south from the teleport spot and go through the door
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Run slightly further south and mine coal and use the deposit box with the coal
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Using the premium skilling zone to make the bars:
Go to the bank and get the inventory with 5 rune bars and the rest coal.
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Use the furnace to the south to make the rune bars
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Put bars in the bank and repeat.
How to use the crafting guild to make the bars:
Use the teleport tab to get to the crafting guild.
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Open guild door
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Use the bank in the south corner to get your inventory like mine
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Smelt your bars in the north-west corner of crafting guild.
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Thanks for looking at the guide