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Smoothly slide tiles along rows and columns of a grid of mineral crystals. Match pairs of mineral crystals with the same Mohs hardness to remove them from the board. Clear the board in as few moves as possible with the most points. Gain extra points by making more than one match per move.
Just by playing you can learn the names of common minerals, their Mohs hardness values, shapes and colors.
Clear the board for a bonus activity that will test your knowledge of the Mohs hardness scale.
Challenging tiled puzzle that will tease your brain with random tile arrangements and improve your problem solving skills. Exercise your mind using visual agility, memory, pattern recognition, visualization and prediction.
Two levels: one easy, one hard. No in-app purchases required. Virtually unlimited arrangements, select a new arrangement at any time.