Mining is by far the most popular ability in Runescape. Why is that? Because mining is an excellent method to RS gold earn money. The money starts racking in at the age of 15!! Mining is a profitable business that makes lots of money. Below are some mining areas:
Note: If I refer to the Dwarven mining mines, I will include the mining guild. To mine pure essence or rune, you must have completed the Rune Mysteries quest. Once you've completed the quest, Audbury will teleport you to the rune/pure essence mine. Dwarven mines (located near Falador) contain a large amount of iron rock. Iron ore is also found in the mine north of Al-Kharid.
There are many locations for coal mining. It is possible to go north-west of Edgeville to a coal mine which has 34 rocks (Downside is is located in the wilderness). South-west Lumbridge is another great spot for coal mining. The Dwarven mine, which includes the mining guild, is still the most suitable place to mine coal.
Places where Mithril can be mined include south-west of the lava maze north of Al-Kharid south Crandor island south-west of Lumbridge, and of course the Dwarven mines (including the mining guild) There are only 2 runite rock formations in the non-member world! They are located to the north-east of the Lava-Maze. Mining is an art that can quickly earn you money. It's a skill that I would strongly recommend!
There are two types of cooking: cooking fish/meat and cooking bread/pies/stews/pizzas/cakes. Raw fish/meats can be more profitable than cooked. This is because people value the experience cooking, more than money, so they will spend more money to purchase uncooked fish. Cooking fish/meat is not profitable.
On the other hand cooking bread/pies/pizzas/stews/cakes is very profitable. It is not necessary to spend money to make these. For example, to make stew, you'll need a bowl (4 coins), potato (you can find it in a field for free), and meat (free). A stew bowl is worth 4 coins. This is how you just got 159 coins. It's not a huge amount, but it adds up, quickly.
Simply, runecrafting involves the conversion of pure essence/runes into runes. Because members can create all the expensive high-lvl runes, it's a lucrative business. Non-members are limited to OSRS buy gold crafting the basic runes which are almost worthless.