Gem Magic Rulesheet

Gem Magic system

Source: There is a magical field around the planet like a magnetic field. It’s generated in the world’s core. Some places are field hotspots and have more magic there. People are drawn to these areas and build cities nearby. Magic tends to break down structures after a while, so nobody builds right in it.

People draw on the field using metals and gems. Everybody has a little magic in them, but some people are more attuned to the field than others. Certain spells require certain reagents, focuses, etc.

Basically, take your modifiers and flavor them with a gem. Any spell that uses a modifier can be said to use that gem.

Strength: topaz (evocation)
Dexterity: sapphire (transmutation)
Constitution: ruby (conjuration)
Intelligence: diamond (enchantment)
Wisdom: emerald (divination)
Charisma: obsidian (abjuration)

Amythyst (illusion)

Opal (necromancy)


Diamond: focuses thoughts and psychic energy.

Diamond: focuses thoughts and psychic energy.

Main stat: intelligence

School: enchantment

Classes that benefit: Druid, wizard, rogue

Virtue: Love
Vice: hate



Ruby: used for life, blood, healing, manipulating life force

Ruby: calling, healing, creation, teleportation

Main stat: constitution
School: conjuration

Classes that benefit: barbarian, fighter, sorcerer

Virtue: Kindness, gentleness
Vice: causes hurt



Emerald: manipulates plants and growing things

Emerald: find truth, scrying, predict the future, find hidden things, foil deceptive spells

Main stat: wisdom
School: divination

Classes that benefit: cleric, Druid, paladin, warlock, wizard

Virtue: hope
Vice: poison, despair



Sapphire: manipulates air, water (chaos, malleability)

Sapphire: manipulates air, water (chaos, malleability)

Main stat: dexterity

School: transmutation

Classes that benefit: bard, monk, ranger, rogue

Virtue: Creativity
Vice: chaos, insanity



Topaz: manipulates the earth, stone, soil, lava

Topaz: manipulates the earth, stone, soil, lava

Main stat: strength

School: evocation

Classes that benefit:

Virtue: Faithfulness, loyalty
Vice: obsession



Obsidian: obscures or counters spells

Obsidian: obscures or counters spells

Main stat: charisma

School: abjuration

Classes that benefit: bard, cleric, paladin, sorcerer, warlock

Virtue: protection and defense
Vice: imprisonment



Amethyst: General energy-gathering focus, used in conjunction with other gems, good at fooling the senses

School: illusion


Opal: used in curses–shifting, unstable, manipulating life force

School: necromancy



Gold: corresponds to diamond, ruby, emerald. Enhances and focuses casting, can grant up to +2 to modifiers, but costs 1000g per gem set


Silver: sapphire, topaz, obsidian
Same as above, but grants +1 to modifiers, 600g per gem set


Bronze, steel, copper, iron, etc: can be used for any casting but with less pure effect, 0 modifier, 200g per gem set



Pictures and runes are etched onto the settings around gems. These can add up to Xd6 damage or effect to any attack roll, but you have to draw a picture and show it to the DM. 1d6 added for awesomeness of runes and pictographs used.


Gem cuts:

Different cuts of gems can be used to explain how, for example, a diamond could cast a fireball while a different diamond casts healing surge. Extra inspiration points for anyone who bothers to look up gem cuts and mention this during casting.

Other notes:

A person can exhaust themselves from too much magical use. Gems can be depleted. Precious stones can recharge themselves, but semi precious stones often have only one or two uses before they go dark.

Uncut more general use, not focused

Jewel cutters revered



People trade in uncut gemstones and semiprecious stones. This and metals are used as currency.

Towns build gem/stone/metal totems to enhance health, fertility, etc in the surrounding area.

Gems are also used to power machines, provide light, do all the ubiquitous tasks of electricity in society.

Ports traffic in gem trade from other countries. Our main country of interest has rich silver and semi-precious stone mines.