Two-tone gold is any type of decorative piece that is created using two different types of gold. The color and purity of this precious metal can be altered when combined with other metal alloys, such as silver, copper, and zinc. Tinting methods are often used in conjunction with various design techniques to create woven patterns, flowers, and accentuate intricate details.
Gold in its purest form is very soft and malleable. Its natural pliability makes it unusable in metalwork by itself. When combined with other metal alloys, however, gold may be sufficiently strengthened to become hard and hold a given shape. The finished color of the gold piece can be altered based on the type of metal with which it is bonded.
The most commonly used type of gold is yellow. This color is typically achieved through a combination of pure gold, copper, and silver. The resultant bright, yellow metal is often the foundation for two-tone gold pieces, as well as three-tone and multi-metalwork creations. The term karat when applied to gold is a measure of the metal's purity. Larger numbers indicate that the referenced piece is very pure, with 24 karats being the most pure.
White gold is frequently used in two-tone gold pieces. This color is created by blending gold with silver, zinc, nickel, and occasionally palladium. The finished product often resembles silver, but also provides a faint yellow luster.
Gold can also be found in shades of rose, black, and green, though these are often more difficult to locate. Rose tints are achieved by increasing the amount of copper present in the blend. Black gold contains a mixture of sulfur and oxygen and often appears slightly grey in hue. Gold provides a greenish tinge when mixed with different amounts of copper, zinc, and silver, and is more noticeable when juxtaposed with contrasting colors than when designed as a stand alone piece.
Artwork, jewelry, and clothing accessories may all be designed using two-tone gold work. Each blended shade of gold may be used similarly to paint colors by the artist to create an overall work of art. Delicate rose and pink colored petals can form the base of a metal rose that is flanked by green leaves and mounted on a band of gold, for example. These two-tone pieces may be combined with diamonds and gems to create larger stone settings. This precious metal is also frequently designed together with silver to create a two-tone effect in jewelry, though such pieces are not 100% gold.