GemologistG 10

Easiest with a touch screen, but still very doable with a mouse. For this achievement, enter Dash mode. Every time you reach a speed chain bonus multiple of 15 (e.g. 15, 30, 45, etc., you will receive a special tile at random. If/when you receive a Gem tile, save this for your second-to-last match for that puzzle. The reason for this is that you then only have to make a single match, and this will count as the first of your 3 completed puzzles, so functionally, you only have to complete 2. If you use it as your last match, gem mode will not be considered active until the next puzzle, so you will have to complete 3 full puzzles.