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Alloying up 14K to 18K

I have some 14k scrap gold, and my dad is giving me a 1/2 oz gold
coin…which I was told was 22k. If I have equal parts of both the
14k and the coin will it alloy out to 18k…my math says it
will…but I figured I should just ask for a second opinion since I
haven’t seen any alloying equations that have this info


Brandy, I get the same. Here’s what I did:

5 dwt (say) of 14kt. x .585 = 2.92 dwt. 24k
5 dwt 22kt. x .916 (22kt.) = 4.58 24kt.
2.92 + 4.58 = 7.5 total 24 kt.
5 14kt. + 5 22kt. = 10 dwt. 18kt x .75 = .750

Oppi Untract’s book has several different tables for conversion, how
to alloy from 22k to 10 kt, 14k to 18k, 10k to 14k, ect.

Richard Hart

If you were trying to up the carat rating from 9ct to 18ct you would
add an equal amount of 24ct to the 9ct. 14ct to 18ct needs less 24ct.

Say we have 10g of 14ct. 4.15g of that would be alloy material. To
work out how much 24ct you will need to add, you need to make that
4.15g = 25% of the total finished weight. If you add 6.6g of 24ct to
14ct, you end up with a total weight of 16.6g, 25% of that = 4.15g in
alloying material. You now have 18ct (75% gold content)