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Posted by Esslinger Staff

 

To figure out how much gold you should add to karat up:

Take your starting weight and figure exactly how much alloy is contained. Divide this weight by the alloy factor of the karat you want to go up to. This will give you the total weight of the desired karat that you will end up with. Subtract from this total weight your starting weight, and this will you you much fine gold to add.

 

                                         Example, 10K to 14K:
 Starting Weight 10K  350 T/oz
 x .5833
 Total oz. alloy contained  204.155
 Divide by  .41667
 Total amount of 14K made with this amount of alloy  489.97 T/oz
 Subtract starting weight  -350.00
 Amount of fine gold to be added  139.97 T/oz

 

 

 

To figure out how much gold you should add to karat down:

Take your starting weight and figure exactly how much fine gold is contained. Divide this number by the gold factor of the karat you want to go down to. This will give you the total weight of the desired karat that you will end up with. Subtract your starting weight from this number, and that will tell you how much alloy to add.

 

                                              Example, 14K to 10K:
 Starting Weight 14K  500.00 T/oz
 x .5833
 Total fine gold contained  291.65 T/oz
 Divide by  .41667
 Total amount of 10K made with this amount of fine gold  699.95 T/oz
 Subtract starting weight  -500.00
 Amount of alloy to be added  199.95 T/oz

 

 

Simple Conversion Factor to Karat Up or Down

 

Reducing Factors

To reduce karat: Find reducing factor at intersection of “Karat on Hand” and “Karat Wanted. Multiply the weight of your karat gold on hand by the reducing factor. This gives you the weight of alloy you must add to reduce to karat wanted.

 

Karat Wanted
Karat
On
Hand

24K
18K
14K
18K 
.333333
14K 
.714287
.285715
10K 
1.400
.8000
.4000

 

 

Reducing Factors

To raise karat: Find raising factor at intersection of “Karat on Hand” and Karat Wanted”. Multiply the weight of your karat gold on hand by the raising factor. This gives you the weight of fine gold you must add to raise to karat wanted.

 

Karat Wanted
Karat
On
Hand

10K
14K
14K 
.400
18K 
1.333336
.666667

 

22.472

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