A South African mother and two accomplices were sentenced to life imprisonment on Thursday for trafficking her then-six-year-old daughter, in a case that gained nationwide attention since the child went missing last year.

Kelly Smith, her boyfriend Jacquen Appollis, and their friend Steveno Van Rhyn were convicted of kidnapping and trafficking the girl, Joshlin Smith, after she disappeared from a small town in the Western Cape.

In a trial that shocked the country, a witness said Kelly Smith told her that she had sold her daughter to a sangoma, or traditional healer, for 20,000 rand ($A1744) and that the girl was desired for her “eyes and skin”.

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Joshlin Smith has still not been found, despite an extensive police search.

Announcing their sentences on Thursday, high court judge Nathan Erasmus said the fact Smith, Appollis and Van Rhyn were drug users was no excuse.

“There is nothing that I can find that is redeeming and deserving of a lesser sentence than the harshest I can impose,” Erasmus said.

For kidnapping, the three were given 10-year jail terms.