Gold and gilding

We use 18 carat gold plating on many of our steel jewellery. The gilding stays well, but fades slightly over the years. 

Carats measure the concentration of gold in the mass. One carat is one twenty-fourth (1/24) of the weight. A 24 carat product is almost 100% gold while 18k is 75% gold.

According to Finnish precious metal regulations, the minimum content should be at least 585 parts per thousand by weight, which is slightly higher than 14k gold.