As the most malleable of all precious metals, gold is an excellent choice when crafting designs with very intricate details. Plus, it’s resistant to rust, tarnishes, and corrosion. Pure gold is too soft for everyday wear, so it’s alloyed with a mixture of silver, copper, and a trace of zinc, to give it strength and durability. This hardens the final product enough to last for many generations. Karatage, denoted by a number followed by “k”, indicates purity, or how much of the metal in a piece of jewelry is gold. Karatage is expressed in 24ths, making 24k gold the highest karat gold. It has a rich and luxurious gold-yellow color, but unlike 14k or 18k gold, it’s far too malleable for everyday wear.
Gold is commonly stamped with what’s known as a hallmark. The hallmark indicates the amount of pure gold content, and sometimes denotes the date of completion and country of origin. And under federal law, gold jewelry must be accompanied by a maker's mark or registered trademark.
COLOR OF GOLD
Although it’s true that the color of pure gold is yellow, gold jewelry or objects are almost always alloys. The metal they are alloyed with changes their color to a variety of shades depending on:
- The type of metal alloys included
- The percentage of each metal alloy
- The metals used to alloy gold, which includes: zinc, copper, nickel, iron, cadmium, aluminum, silver, platinum, and palladium
A mixture of silver, copper, pure gold (and a trace of zinc) gives yellow gold jewelry its rich shine. Although the percentages of each metal used to create the alloy vary, all formulas start with 75% pure gold for 18k gold and 58.3% for 14k gold. The result gives off a classic warm glow that makes an especially good setting for lower color grade diamonds with a faint yellow tint. In 14k yellow gold, which is slightly less rich in color than 18k yellow gold, it’s important to note not only the difference in color between the two karats but also the difference in durability and hardness. 18K is softer and will, therefore, show scratches more readily. 14K is harder which makes it a little more resistant to scratching.
In order to give white gold jewelry its modern silvery-white color, pure gold is often alloyed with a mixture of nickel, or palladium and silver, plus other whitening alloys. The piece is then plated (meaning it’s covered with a layer of another metal) with an extremely hard element called rhodium. While rhodium plating is relatively long-wearing, some occasional replating may be required. It’s not uncommon after a few years to see a slight champagne-colored tint in your white-gold jewelry. This can be a sign that your jewelry needs replating to restore its original whiteness. We recommend routine cleaning and annual maintenance.
The romantic pink hue of rose gold jewelry is created by using a copper alloy. The more copper in the alloy, the rosier the hue. Rose gold has the same amount of pure gold as yellow or white gold. What’s different is the ratio of other metals that make up the remaining percentage of the alloy mix. Rose gold is a beautiful and unique choice for engagement rings, and its modern-vintage appeal has been a hot trend in the last few years. The preference of one karat over another comes down to whether people want a lighter (18k) or slightly deeper (14k) rose color for their setting or band.