Diamond

is an object in the game.

This object is consumed upon usage.

How to get it
The Bear is blocking the cave's entrance. You need to neutralize it first. You can do one of the followings: After the Bear has gone, you can go inside the grab the Diamond.
 * Give the Bear Poppies Soup or Rum: These will intoxicated the Bear, make it go away or collapse.
 * As the Bandit, shoot the Bear with Pistol and Acorn: This will hurt the Bear and make it go away.
 * As the Granny, smack the Bear with the Broom: This will hurt the Bear and make it go away.

Usage
can be used for:
 * Getting Coin Bag: the King will give you a Coin Bag after you gave him Diamond. Unlock the "King's Jewel" achievement.
 * Entertaint the Merchant: As the Devil, you can entertain the Merchant, using the Diamond.
 * Buying Sword: You can buy the Sword by giving the Merchant a Diamond.