KDM: Gold Jewellery from some places are marked with a KDM stamp which means that the Jewellery was soldered with Cadmium. Cadmium called 'Kadium' in some places and marked as KDM was traditionally used in soldering of gold jewellery for its good properties of liquidity and melting at lower temperatures,Jewellers in many parts of the world now use gold solders,which are free from Cadmium.Also note that using any types of gold solder either KDM (Cadmium) or other gold solder, to make the jewellery does not guarantee the purity of gold, as the purity is a representation of the percentage of gold in any metal. Cadmium - is used in soldering gold.Control of KDM soldering on gold may vary from one country to another.
Recently Americans and Europeans are using Zinc in place of KDM in jewellery making
916:-The carat (abbreviation ct) is a measure of the purity of gold and platinumalloys.
Standard gold is 24 carat (100% pure gold).
22 carat or ornamental gold is called 916 gold , ( 91.6%) pure gold and the rest includes metals like copper and silver to get tensile strength and also workability on gold.
There are few ways to find out the difference between 22karat and 24karat gold. They are:
* Difference in weight (24karat gold’s weigh 19.4gm/cm3)
* Using Karat machine.