Gold bars tend to be less costly to produce and, therefore, generally sell for closer to gold's current spot price. By comparison, gold coins are costlier to mint due to their intricate designs. They're also considered collectible, which can lead to higher premiums for coins that are seen as especially valuable.

Most experts recommend limiting your gold investment to 10% or less of your overall portfolio. The range between 1% and 10%, however, will often vary based on your age and overall investor profile.