Black Belt 20%
Black Glasses 20%
Bug Gem 50%
Charcoal 20%
Dark Gem 50%
Dragon Fang 20%
Dragon Gem 50%
Draco Plate 20%
Dread Plate 20%
Earth Plate20%
Electric Gem 50%
Fighting Gem 50%
Fire Gem 50%
Fist Plate 20%
Flame Plate 20%
Flying Gem 50%
Ghost Gem 50%
Grass Gem 50%
Ground Gem 50%
Hard Stone 20%
Ice Gem 50%
Icicle Plate 20%
Insect Plate 20%
Iron Plate 20%
Magnet 20%
Meadow Plate 20%
Metal Coat 20%
Mind Plate 20%
Miracle Seed 20%
Mystic Water 20%
NeverMeltIce 20%
Normal Gem 50%
Posion Barb 20%
Posion Gem 50%
Psychic Gem 50%
Rock Gem 50%
Sharp Beak 20%
Silk Scarf 20%
Siver Powder 20%
Sky Plate 20%
Soft Sand 20%
Spell Tag 20%
Splash Plate 20%
Spooky Plate 20%
Steel Gem 50%
Stone Plate 20%
Toxic Plate 20%
Twisted Spoon 20%
Water Gem 50%
Zap Plate 20%
http://bulbapedia.bulbagarden.net/wiki/Type-enhancing_item