Barium-Calcium Ferrite Disc Magnet: 0.09 mol BaCO3 and 0.01 mol CaCO3 (Went, Philips 1956, Ex. 19)

A ceramic magnet with a tenth of the barium replaced by calcium: 0.09 mol barium carbonate and 0.01 mol calcium carbonate to 0.6 mol iron oxide, made as in Example 18: milled, presintered at 1000 °C, milled again, formed and passed through a 1330 °C furnace in 10 minutes. Went's rod held 1,705 gauss with a coercive force of 1,110 oersted. Source: J. J. Went, G. W. van Oosterhout and E. W. Gorter (Philips), US 2,762,777 (1956), Example 19. They sintered rods; discs and the magnetising are ours. Picture: ferrite magnets, Omegatron, Wikimedia Commons, CC BY-SA 3.0.