An ancient decorative technique, 'keum boo' means attached gold in Korean. 24 gold is melted down, rolled and hammered out into very fine sheets almost 2.5 microns thick in the workshop. Although fine, this is 25x thicker than gold leaf that is used for gilding, and thicker than regular gold-plating.

For the 24ct gold to permanently bond with sterling silver, a process called depletion is needed beforehand, to produce a layer of fine silver (999) on the top. Depletion involves a repeated process of heating, cooling and pickling the silver, to remove oxides and leave behind the pure silver on the top.

The fine pieces of gold are then applied, by hand, to the surface of silver, with a combination of heat & burnishing, which produces a diffusion bond of the two precious metals.

When silver is oxidised and darkened down, it produces a much stronger contrast between the metals as the gold does not oxidise.