About Platinum Diamond Mountings and Mountings Employed in Earlier Times

Platinum Mountings

Diamonds have been mounted into gold jewelry in the richer countries of the world for centuries, but an examination of the collections of old jewelry in the great museums of the world will convince any one that this ancient work is of interest and value only to the student of antiques. These ornaments were invariably of gold. In work of a more recent date, platinum, although used to a limited extent for about thirty years, has been used to a marked degree only since about 1900. In the evolution of present-day diamond jewelry, however, platinum has been the metal which has increased steadily in favor, until it is now practically the only metal used for the most elaborate and artistic creations. Platinum was discovered in South America in 1735 and in Russia in 1819. It has also been found in Canada and Australia. About nine tenths of all produced in the world now comes from Russia. Very little, however, is found, only about one per cent of platinum since its discovery in proportion to gold found in the same period. It is generally found in the sand of placer mines and the usual yield is one ounce of platinum to a ton of sand.

For use it must be alloyed with iridium and when properly alloyed is very hard and retains a fine brilliant finish. As iridium is far more expensive even than platinum, some manufacturers, in order to secure platinum at lower price, have not used enough iridium in their alloy, which has resulted in the metal becoming soft and turning dull or leady in color. Platinum of standard hardness of alloy weighs nearly sixty per cent more than fourteen-carat gold, and while fourteen-carat gold costs sixty-four cents per pennyweight, platinum now costs about $2.50 per pennyweight.

Comparison of Cost of Material in Mountings

In computing as an example the value of a diamond mounting, it might be said that a diamond mounting weighing ten pennyweights would cost for the gold $6.40; a mounting of the same size in platinum would weigh nearly sixteen pennyweight and cost nearly $40 for the material.

The cost of working platinum is also far greater than that of gold, but its brilliant finish and hardness and harmonizing color make it far the best metal for fine diamond and pearl mountings.