Converting 22ct gold to 18ct gold?

Question

I have 100 gms of 22ct gold now i want to convert it to 18ct gold, so how much alloy i have to add?

Answer 1

You have 22/24 = 0.9167 and you want 18/24=0.75.

M1C1=M2C2

100*0.9167= M2*0.75

M2 = 100*0.9167/0.75

M2 = 122.23g

You increase the mass of your gold from 100g to 122.23g and you will have 18 carat gold.

Answer 2

you have 22/24 so thats 91.667% or 91.6667 grams AU and you need to dilute it to 75% but still maintain the 91.667 so the total needs to be of the final mixtue 91.667/.75  or 22/24/ (18/24) = 22/18 =1.22 time 100 is 122.22 gms so 122.222 - 91.6667 = 30.5556 grams.

Answer 3

x is the amount of alloy to add.

there are 22/24 x 100 grams of 24K gold in your 22K gold,

2200/24 =  91.6666 grams of 24K gold,

so 91.66666 / (100 + x ) = 0.75

91.6666 = 0.75 (100 + x)

91.6666  = 75 + .75x

.75x = 16.6666

x = 22.2222 grams

check 91.66666 / 122.2222 = 0.75

Grandpa

Answer 4

Your local jeweller should be able to do it for you.He would know the right quantities of other metals to be

added to make 18 ct gold out of 22 ct gold.

Answer 5

give it to your jeweller for redesigning the jewwlary He will do it for you and still tell you that it is still 22 carat. Then you go to test at hallmark centre you will get it 18carat. easy is not it.