Method for producing calcium of high purity

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The present invention is a method for producing calcium of a high purity, the method being characterized by the following : performing first sublimation and purification by introducing a calcium starting material having a purity, excluding the gas component, of 4 N or less to a crucible of a sublimation vessel, subjecting the starting material to sublimation by heating to 750 to 800ºC, and causing the product to deposit (evaporate) onto the inside walls of the sublimation vessel; and then, once the calcium that has been subjected to first sublimation and purification is recovered, performing second sublimation and purification by introducing the recovered calcium again to the crucible of the sublimation vessel, heating the calcium to 750 to 800ºC, and causing the product to similarly deposit (evaporate) on the inside walls of the sublimation vessel thereby recovering calcium having a purity of 4N5 or greater. The goal of the present invention is to provide a technology with which calcium that has been brought to a high purity can be obtained with stability in order to be used for the production of lanthanum of a high purity, as well as to be used as a reducing agent for other rare earth elements, a desulfurizing agent or a deoxidizing agent for metals, and as a getter for high vacuum pumps.