There are several different types of Diamonds in Luigi's Mansion. They can be found in many different places. Speedy Spirits, Gold Mice and Treasure Chests can also hold them. Here is a list of every single one you may be looking for:
- Silver Diamond, a diamond that is worth 2,000,000G(s)
- Red Diamond, a diamond that is worth 5,000G(s) (The same amount as a Coin)
- Gold Diamond, a diamond that is worth 20,000,000G(s)
- Stone, a type of treasure that is also known as Round Diamonds.