I think I may have found the problem.
public static final Item rubyHelmet = new ItemGemHelmet(5050, EnumArmorMaterialGem, ModLoader.addArmor("ruby"), 0).setItemName("helmetRuby").setIconIndex(12);
public static final Item rubyPlate = new ItemGemPlate(5051, EnumArmorMaterialGem, ModLoader.addArmor("ruby"), 1).setItemName("plateRuby").setIconIndex(28);
public static final Item rubyLegs = new ItemGemLegs(5052, EnumArmorMaterialGem, ModLoader.addArmor("ruby"), 2).setItemName("legsRuby").setIconIndex(44);
public static final Item rubyBoots = new ItemGemBoots(5053, EnumArmorMaterialGem, ModLoader.addArmor("ruby"), 3).setItemName("bootsRuby").setIconIndex(60);
public static final Item onyxHelmet = new ItemOnyxHelmet(5054, EnumArmorMaterialOnyx, ModLoader.addArmor("onyx"), 0).setItemName("helmetOnyx").setIconIndex(13);
public static final Item onyxPlate = new ItemOnyxPlate(5055, EnumArmorMaterialOnyx, ModLoader.addArmor("onyx"), 1).setItemName("plateOnyx").setIconIndex(29);
public static final Item onyxLegs = new ItemOnyxLegs(5056, EnumArmorMaterialOnyx, ModLoader.addArmor("onyx"), 2).setItemName("legsOnyx").setIconIndex(45);
public static final Item onyxBoots = new ItemOnyxBoots(5057, EnumArmorMaterialOnyx, ModLoader.addArmor("onyx"), 3).setItemName("bootsOnyx").setIconIndex(61);
public static final Item sapphireHelmet = new ItemSapphireHelmet(5058, EnumArmorMaterialGem, ModLoader.addArmor("sapphire"), 0).setItemName("helmetSapphire").setIconIndex(14);
public static final Item sapphirePlate = new ItemSapphirePlate(5059, EnumArmorMaterialGem, ModLoader.addArmor("sapphire"), 1).setItemName("plateSapphire").setIconIndex(30);
public static final Item sapphireLegs = new ItemSapphireLegs(5060, EnumArmorMaterialGem, ModLoader.addArmor("sapphire"), 2).setItemName("legsSapphire").setIconIndex(46);
public static final Item sapphireBoots = new ItemSapphireBoots(5061, EnumArmorMaterialGem, ModLoader.addArmor("sapphire"), 3).setItemName("bootsSapphire").setIconIndex(62);
I need to replace those ModLoader methods with Forge methods, but I have no idea what the Forge methods are for that.