My latest project is heavily inspired by Diablo II, particularly the item system. At the moment I'm working on gems for socketed items. I'll have the following gem colors:

• red
• pink/violet
• purple
• cyan
• green
• chartreuse
• orange
• white/light gray
• black/dark gray

What effects would you link to the colors? My game design is still in progress, so you can feel quite free with suggestions. The only fixed stats that I have are strength, dexterity, intelligence, wisdom. Effects are fire, lightning/shock and cold/ice. For effects there can be both, causing and resistance to.

Somewhat likely to be included are acid, fear and confusion effects.

Secondary stats are mana, and life (f(wis,int), f(str,dex))

Then of course, physical damage and damage reduction, blocking for shields, and defense for armor.

Maybe more which I have forgotten ...

E.g. red gems could affect strength (and with that life) in armor, give fire attacks (weapons) and cause fire resistance (helms/shields) .. or something.

Just let me know what comes to your mind. Also I need names for the gems. The names should match the suggested effects and colors, somehow or somewhat, or just be interesting. E.g. ruby, hell obsidian, starlight shard, northern azurite, aquamarine ...

 PS: special rocks and skulls and such will be added later, but I have no clear idea about them yet ...