This unique StoneThree technology is the first and only sensor to provide bubble size, bubble rise rate in the flotation cell and Gas Holdup. This opens up a new dimension in the process of monitoring and controlling individual flotation cells to optimize the dosage of reagents. The innovative camera and lighting setup provides in-situ images (within the flotation cell) with high frame rate (FPS) and excellent image quality makes it possible to track bubbles inside the tank. The cell-immersed solution, encapsulated in an abrasion resistant housing, will operate for years with minimal maintenance requirements. Very simple installation provides remote commissioning.