Slayer Coins
Slayer Coins are earned by completing 
Slayer Tasks. A guide explaining Slayer Task mechanics can be found here. Monsters killed for Slayer Tasks earn Slayer Coins and Slayer experience points equal to 10% of the slain monster's hitpoints. Note that Slayer Tasks are the only way to earn Slayer Coins, and killing monsters in a Slayer area that aren't the player's current Slayer Task will not earn them Slayer Coins.
Value
Slayer Coins cannot be directly sold for a profit. However, several items from the 
Shop can be bought and sold individually for a profit.
Resale value
Below is a table that shows the 5 most profitable items that can be bought from the Shop and can be resold for 
Coins.
| Purchase | Cost | Requirements | GP Value | GP per SC | |
|---|---|---|---|---|---|
 |  Bountiful Resupply | 150,000 | Level 110 | 8,323,500 | 55.49 |
 | Plentiful Resupply | 75,000 | Level 100 | 2,165,900 | 28.88 |
 | Generous Resupply | 20,000 | Level 75 | 483,800 | 24.19 |
 | Standard Resupply | 10,000 | Level 50 | 221,500 | 22.15 |
 | Basic Resupply | 5,000 | None | 91,600 | 18.32 |