Runescape Magic is based off magical stones called RuneStones. (Usually referred to as Runes.) It takes a certain combination of Runes to perform a certain spell. You can know what runes do what spell when you look in your Runescape Magic spell book. There are many different types of Runes. Some are more expensive than others. I will name a few of the various types of runes.
Twenty Types of Runes 1.) Air Rune 2.) Water Rune
3.) Mist Rune
4.) Earth Rune
5.) Dust Rune
6.) Mud Rune
7.) Fire Rune
8.) Smoke Rune
9.) Steam Rune
10.) Cosmic Rune
11.) Law Rune
12.) Nature Rune
13.) Mind Rune
14.) Body Rune
15.) Lava Rune
16.) Chaos Rune
17.) Death Rune
18.) Blood Rune
19.) Astral Rune
20.) Soul Rune These magical stones were crafted years ago by the ancestors of Runescape. They are infused with magical powers from the land. As I said above, it takes a certain combination of Runes to do certain spells; I will list every combination in the normal Spell book in order.
Combination of Runes for Certain Spells Wind Strike - 1 Mind, 1 Air
Confuse - 1 Body, 2 Earth, 3 Fire
Water - Strike 1 Mind, 1 Air, 1 Water
Enchant Level-1 - 1 Cosmic, 1 Water
Earth - Strike 1 Mind, 1 Air, 2 Earth
Weaken - 1 Body, 2 Air, 3 Earth
Fire - Strike 1 Mind, 2 Air, 3 Fire
Bones to Bananas - 1 Nature, 2 Water, 3 Earth
Wind Bolt - 1 Chaos, 2 Air
Curse - 1 Body, 2 Water, 3 Earth
Low Level Alchemy - 1 Nature, 3 Fire
Water Bolt - 1 Chaos, 2 Air, 2 Water
Varrock Teleport - 1 Law. 3 Air, 1 Fire
Enchant Level-2 - 1 Cosmic, 3 Air
Earth Bolt - 1 Chaos, 2 Air, 3 Earth
Lumbridge Teleport - 1 Law, 3 Air, 1 Earth
Telekinetic Grab - 1 Law, 1 Air
Fire Bolt - 1 Chaos, 3 Air, 4 Fire
Falador Teleport - 1 Law, 3 Air, 1 Water
Crumble Undead - 1 Chaos, 2 Air, 2 Earth
Wind Blast - 1 Death, 3 Air
Superheat Item - 1 Nature, 4 Fire
Camelot Teleport - 1 Law, 5 Air
Water Blast - 1 Death, 3 Air, 3 Water
Enchant Level-3 - 1 Cosmic, 5 Fire
Iban Blast - 1 Death, 5 Fire
Ardougne Teleport - 2 Law, 2 Water
Earth Blast - 1 Death, 3 Air, 4 Earth
High Level Alchemy - 1 Nature, 5 Fire
Charge Water Orb - 3 Cosmic, 30 Water, 1 Orb
Enchant Level-4 - 1 Cosmic. 10 Earth
Watchtower Teleport - 2 Law, 2 Earth
Fire Blast - 1 Death, 4 Air, 5 Fire
Charge Earth Orb - 3 Cosmic, 30 Earth, 1 Orb
Claws of Guthix - 2 Blood, 4 Air, 1 Fire
Saradomin Strike - 1 Blood, 4 Air, 2 Fire
Flames of Zamorak - 2 Blood, 1 Air, 4 Fire
Wind Wave - 1 Blood, 5 Air
Charge Fire Orb - 3 Cosmic, 30 Fire, 1 Orb
Water Wave - 1 Blood, 5 Air, 7 Water
Charge Air Orb - 3 Cosmic, 30 Air, 1 Orb
Vulnerability - 1 Soul, 5 Water, 5 Earth
Enchant Level-5 - 1 Cosmic, 15 Water, 15 Earth
Earth Wave - 1 Blood, 5 Air, 7 Earth
Enfeeble - 1 Soul, 8 Water, 8 Earth
Fire Wave - 1 Blood, 5 Air, 7 Fire
Stun - 1 Soul, 12 Water, 12 Earth
If you want to work in this skill well, I would like to suggest you become a Rune Crafter as well first,then you can needn't have to pay as much.About the Author:
Twenty Types of Runes 1.) Air Rune 
Combination of Runes for Certain Spells Wind Strike - 1 Mind, 1 Air 