If you are a South African citizen who is looking to apply for an ancestral visa for immigration purposes:
Countries which issue ancestral visas require that the PERSON applying for such visa, have a GRANDparent (or sometimes parent) born in that country.
You also have to provide official documents (birth, marriage and / or death certificates) showing your line of descendant from the grandparent and/or parent.
The certificate MUST be a VAULT copy (which is a photocopy of the original entry in the Registrar Book held by the Department Of Home Affairs). A vault copy will have two pinkish stamps of that department. One is a date stamp and the other states a "true copy of the original". FULL or UNABRIDGED certificates WILL NOT be accepted.
If you engage a genealogist to help you trace your ancestry for visa purposes, it is important that you make this fact known to such genealogist.