Specific Gravity & Melting Point

Metal °F °C Specific Gravity Weight in Troy OZ per CU IN
Aluminum 1220 660 2.70 1.423
Antinomy 1167 630 6.62 3.488
Beryllium 2340 1282 1.82 0.959
Bismuth 520 271 9.80 5.163
Cadmium 610 321 8.65 4.557
Carbon 2.22 1.170
Chromium 3430 1888 7.19 3.788
Cobalt 2723 1495 8.90 8.900
Copper 1981 1083 8.96 4.719
Gold 1950 1065 19.32 10.180
18K Green 1810 988 15.90 8.375
18K Yellow 1700 927 15.58 8.211
18K White 1730 943 14.64 7.712
18K Red 1655 902 15.18 7.998
14K Green 1765 963 14.20 7.482
14K Yellow 1615 879 13.07 6.885
14K White 1825 996 12.61 6.642
14K Red 1715 935 13.26 6.986
10K Green 1580 860 11.03 5.810
10K Yellow 1665 907 11.57 6.096
10K White 1975 1079 11.07 5.832
10K Red 1760 960 11.59 6.106
Iridium 4449 2454 22.50 11.849
Iron (Pure) 2802 1539 7.87 4.145
Lead 621 328 11.34 5.973
Magnesium 1202 650 1.74 0.917
Manganese 2273 1245 7.43 3.914
Molybdenum 4760 2625 10.20 5.347
Nickel 2651 1455 8.90 4.691
Osmium 4892 2700 22.50 11.854
Palladium 2831 1555 12.00 6.322
Phosphorus 111 44 1.82 0.959
Platinum 3224 1773 21.45 11.301
15% Iridium Plat. 3310 1821 21.59 11.373
10% Iridium Plat. 3250 1788 21.54 11.349
5% Iridium Plat. 3235 1779 21.50 11.325
Rhodium 3571 1967 12.44 6.533
Ruthenium 4500 2500 12.20 6.428
Silicon 2605 1430 2.33 1.247
Silver 1761 961 10.49 5.525
Sterling Silver 1640 893 10.36 5.457
Coin Silver 1615 879 10.31 5.430
Tin 450 232 7.30 3.846
Zinc 787 419 7.13 3.758

HOW TO DETERMINE SPECIFIC GRAVITIES OF ALLOYS

  1. Find the reciprocal of the specific gravity of each metal in the alloy. This is done by dividing 1 by the specific gravity. For example, the specific gravity of silver is 10.49 and the reciprocal is 1 divided by 10.49 or 0.094966.
  2. Multiply each reciprocal by the number of parts per thousand of that metal to be used.
  3. Add the results of the multiplication together.
  4. Divide 1000 by this total - the answer is the specific gravity of the alloy.

Example*:
Find the specific gravity of 14K yellow gold having 583 parts gold, 104 parts silver, and 313 parts copper.

FIRST FIGURE THE RECIPROCALS OF THE SPECIFIC GRAVITIES:

Fine gold: 1 divided by 19.32 = 0.051759
Fine silver: 1 divided by 10.49 = 0.094966
Fine copper: 1 divided by 8.96 = 0.111617

Fine gold: 1 divided by 19.32 = 0.051759
Fine silver: 1 divided by 10.49 = 0.094966
Fine copper: 1 divided by 8.96 = 0.111617

THEN MULTIPLY:

Fine gold: 583 parts by 0.051759 = 30.128
Fine silver: 104 parts by 0.094966 = 9.876
Fine copper: 313 parts by 0.111617 = 34.956
Total: 1000 75.014

1000 divided by 75.014 = 13.33 (the specific gravity of the alloy)

* The specific gravity for any one karat will naturally vary for each composition.