Palladium is a member of the platinum group. The difference between palladium and the rest of the platinum group is that it is subject to attack by nitric acid and by hot sulphuric acid. It is very soft and malleable and is sometimes beaten into leaf for decorative purposes. Alloyed with gold it results in a very white metal with only a 15 percent concentration. It is used in solder for platinum. Alloyed with ruthenium and rhodium it is suitable for jewelry having the look of platinum but half the weight.