Stone (Luigi's Mansion)

Stones are valuable collectibles found in Luigi's Mansion. There are three different colors of Stones, each with their own name: Ten of each color can be found in the Mansion, totaling 23,000,000G. To find them all, Luigi has to water all the plants he can find, examine a variety of objects such as buckets, gutters and gold chandeliers, catch Speedy Spirits, and light up all the rooms in the mansion except for the third and Basement floor hallways.
 * Blue Stones (500,000G each)
 * Green Stones (800,000G each)
 * Red Stones (1,000,000G each)

However, only five of each color can be found in the PAL version's Hidden Mansion as the majority of Speedy Spirits and Gold Mice drop Blue Diamonds instead.

Gems from Luigi's Mansion's sequel, Luigi's Mansion: Dark Moon, bear a resemblance to Stones, though they serve as a collectible rather than an amount of gold they offer.

Trivia

 * When Luigi obtains a Stone, the sprite of Luigi on the Game Boy Horror is Luigi's jumping sprite from Super Mario All-Stars: Super Mario Bros.