Bubble Alumina is used for the production of high temperature insulating refractories. Whilst possessing limited mechanical properties, bubble alumina is an excellent refractory and insulating material for applications up to 1850 deg C (actual critical temperature is dependent upon the prevailing conditions). Bubble alumina can be used with many types of binders, including refractory cements, silicates, phosphates etc. Alternatively it may be used as a loose fill material. Bubble alumina is available in a range of different fractions, from -5mm down to fines. Screened, step-graded sizes are also available.