Sodium Chloride a help full additive to A.R. reduction's??

I have been going through a book a friend brought me.
Gold Recovery,Properties,and Applications by the D.Van Nostrand Company INC,Edited by Edmund M Wise.
I noticed in a number of there instruction's on wet analytical technique they recommend using Sodium Chloride when you reduce A.R.
They say this will help stop the Au from dropping out of solution prematurely.
I have tried to run lot's both with and with out this additive but have not really had a problem with any of them ether way .
Do you think this is of use or an out dated method?
Regards
Justin

Most likely used to precipitate silver chloride thus cleaning the solution of a worrisome metal.

Geo said:

Most likely used to precipitate silver chloride thus cleaning the solution of a worrisome metal.

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I do not think so,Surly they hydrochloric acid would provide all the chlorine possible well before the point of reduction.
After describing a standard evaporation they go on to say "sodium chloride usually is added to the solution to retard the formation of metallic gold " (P332)
And it is repeated for several variations of A.R. recovery but frustratingly they never explain the action the additive is meant to have on the solution.

This is done more so for classic wet chemical analyses wherein the solution is evaporated down.

The same is done for platinum and palladium; addition of sodium chloride prevents the decomposition to metal or the formation of very in soluble PtCl2/PdCl2 (or its oxides).

Lou

Lou said:

This is done more so for classic wet chemical analyses wherein the solution is evaporated down.

The same is done for platinum and palladium; addition of sodium chloride prevents the decomposition to metal or the formation of very in soluble PtCl2/PdCl2 (or its oxides).

Lou

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Thank you for explaining that for me.
Very Much appreciated.
Just