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Raising Gold Carat - Mathematical Formula


#1

What is the mathematical formula for raising the carat of gold.


#2

Hello,

Here is the formula for raising the karat of gold:

FG = [S ( KW - KS)] / (24 - KW)

FG =fine gold
KS = Karat of the scrap gold
KW = Karat wanted
S = Weight of the scrap gold

For exemple you have 20 gr 10 karat of gold. You want to raise the
karat to 14 karat How many gr.s of fine gold needed?

FG = [20 ( 14 - 10)] / ( 24 - 14) = [20 (4)] / 10 = 80 / 10 = 8gr

This way when you add 8 gr fine gold to 20 gr 10 karat gold, you get
28 gr. 14 karat gold.

Kind regards,
Oya Borahan


#3

Here is the chart we’ve used for years: Hopefully the formatting is
ok, tell me if it’s not

Varying the Karat Content of Alloyed Gold

Reducing the Gold karat by adding metal alloy:

Find the reducing factor at the intersection of “original Karat” and
"Karat Wanted" in the chart below. Multiply the weight of your
original karat gold on hand by the reducing factor. This gives you
the weight of alloy you must add to reduce to the karat wanted.
Alloy needed = Original Gold weight x reducing factor.

EXAMPLE: If you have 9dwt. Of 18K gold and want 10K, Multiply 9 by
.800. Alloy Needed = 9dwt. X .800 = 7.2dwt.

Original
Karat
On Hand
Reducing Factors Karat Wanted
| | 22K | 18K | 14K | 10K | 9K |
| 24K | .091 | .333 | .714 | 1.40 | 1.677 |
| 22K | | .222 | .571 | 1.20 | 1.444 |
| 18K | | | .286 | .800 | 1.00 |
| 14K | | | | .400 | .556 |
| 10K | | | | | .111 |

Raising the Gold karat by adding Fine Gold (24Kt.):

Find the raising factor at the intersection of “original Karat” and
"Karat Wanted" in the chart below. Multiply the weight of your
original karat gold on hand by the raising factor. This gives you
the weight of fine gold you must add to raise to the karat wanted.
Fine Gold needed = Original Gold weight x raising factor.

EXAMPLE: If you have 6dwt. Of 10K gold and want 14K, Multiply 6 by
.400. Fine Gold Needed = 6dwt. X .400 = 2.4dwt.

Original
Karat
On Hand
Raising Factors Karat Wanted
| | 9K | 10K | 14K | 18K | 22K |
| 0K | .600 | .714 | 1.40 | 3.00 | 11.0 |
| 8K | .066 | .143 | .600 | 1.667 | 7.0 |
| 9K | | .071 | 1.50 | 1.50 | 6.50 |
| 10K | | | .400 | 1.333 | 6.00 |
| 14K | | | | .667 | 4.00 |
| 18K | | | | | 200 |

To calculate karat weights not shown in the charts above, use the
formulas below: Alloy Needed = Orig. Gold Wt. x (Orig. Kt. - Kt.
Wanted) / Kt. Wanted Fine Gold Needed = Orig. Gold Wt. x (Kt. Wanted

  • Orig. Kt.) / (24 - Kt. Wanted)