Sauna Heater Stones, Rounded Olivine, 5-10cm, 33lbsRounded Olivine Diabase sauna heater stones resemble nature's rounded stones from the great rapids, bringing a softer tone to your sauna along with multiple benefits. This stone introduces a soft steam method; the pouring water runs easily down to the lower stone layers. This way the water reaches more surface area, generating more steam with a softer touch. This method of using rounded stones on the top layer of the heater works in all sauna heaters.