Diamond Drop is an online puzzle game in which players control a mole that must catch and throw diamonds to get points. Each game level has a time limit within which the player must accumulate enough points to fill up the safe. Points come in the form of gold coins, the number of which would depend on the number of diamonds collected in the game. Diamonds are collected by matching three or more diamonds of the same color together vertically or horizontally.
To match diamonds, players first hold down the left mouse button to make the mole catch all of the same-colored diamonds above the gameplay area. Then, players make the mole move right or left to where there are similarly-colored diamonds. When the mole is in position, players then release the mouse button to toss the diamonds back up. When the same-colored diamonds get into contact with their matching gems, the diamonds disappear and turn into coins, collected in the safe located at the right panel of the game area.
Diamond Drop has a simple and easy-to-use graphical user interface. The mole character is controlled by moving the mouse left and right. There are three gameplay modes to choose from and nine bonuses that can be used in collecting diamonds.