A lightweight insulating refractory brick designed for electric furnace linings, made by the firm Babcox and Wilcocks in the United States, was examined by Amdel to determine its physical and chemical properties, with a view to reproducing an equivalent product by using local materials. A fired refractory of matching composition was then made using a raw material mixture of 78 parts by weight of Cromer clay and 22 parts of whiting, fired at 1360 degrees Celcius for 30 minutes. A planned trial on pre-melt foaming of the raw clay using air or steam was not reported.