Rose gold recipe

[Niamh]

Hi all!
I want to make some 18ct rose gold to put as detailing on a white gold ring, im a bit tight on money but i have 2g of 22ct yellow sat in my workshop and copper in excess. How many grams of copper do I need to add to 2 grams of 22ct yellow to get a strong pink 18ct rose gold please? Thanks

[ps_bond]

It depends on the composition of your yellow... If it's something like Gold 91.67% Silver 5% Copper 2% Zinc 1.33% then it's 1.8334g Au, 0.1g Ag, 0.04g Cu, 0.0266g Zn.

(Broadly, you have 2g * 22/24 of gold, you want to reduce it as a proportion to 18/24 so the total weight of alloy becomes 2* (22/24)/(18/24) )

if you add enough copper to reduce it to 18ct (0.444g additional Cu) then you'll have 4% Ag, 19.8% Cu and 1% Zn - although most of the zinc will fume off anyway if it's in the alloy. Probably more of a pink gold than a rose and it's best to err on the side of caution and make sure your alloy is just over 18ct for hallmarking.

[Niamh]

It depends on the composition of your yellow... If it's something like Gold 91.67% Silver 5% Copper 2% Zinc 1.33% then it's 1.8334g Au, 0.1g Ag, 0.04g Cu, 0.0266g Zn.

(Broadly, you have 2g * 22/24 of gold, you want to reduce it as a proportion to 18/24 so the total weight of alloy becomes 2* (22/24)/(18/24) )

if you add enough copper to reduce it to 18ct (0.444g additional Cu) then you'll have 4% Ag, 19.8% Cu and 1% Zn - although most of the zinc will fume off anyway if it's in the alloy. Probably more of a pink gold than a rose and it's best to err on the side of caution and make sure your alloy is just over 18ct for hallmarking.

Thank you for your help! Very useful information, a pink gold is better then one that tests as copper and tarnishes faster I guess haha! Thanks again