The invention relates to the manufacture of high purity silicon as a base material for the production of e.g. crystalline silicon solar cells. SiCU is converted to Si metal by contacting gaseous SiCU with liquid Zn, thereby obtaining a Si-bearing alloy and Zn-chloride, which is separated. The Si-bearing alloy is then purified at a temperature above the boiling point of Zn. This process does not require complicated technologies and preserves the high purity of the SiCU towards the end product, as the only reactant is Zn, which can be obtained in very high purity grades and continuously recycled.