Pink gold, also known as rose gold or red gold, refers to any gold alloy that contains copper. The copper gives the gold a pinkish hue or reddish tint. Pink gold has become increasingly popular in recent years for jewelry, watches, and other luxury items. But what causes this unique pink color?
The pink color in gold alloys is directly related to the percentage of copper present. Higher copper content results in a deeper pink color. 18K rose gold generally has a 75% gold and 25% copper composition. This provides a light pink color. 14K rose gold contains roughly 58% gold and 42% copper, giving it a darker pink or reddish tone.
The copper atoms mixed with the gold create a crystalline structure that reflects light differently, altering the way the alloy absorbs and reflects light. The copper absorbs blue and yellow wavelengths, causing the reflected light to take on a pinkish appearance.
History of Pink Gold
Gold is commonly mixed with metals like silver, copper, and zinc to create different colored gold alloys. Pure 24K gold is very soft and easily scratched or damaged. Alloying gold with other metals makes it more durable for use in jewelry and other applications.
The earliest examples of rose gold jewelry come from ancient Egypt, where it was known as “Russian gold” in the 19th century. At that time, the Russian gold color was achieved by mixing 18K yellow gold with just 5-6% copper. This resulted in a very pale pink gold. Higher copper content rose gold jewelry became popular during the 18th and 19th centuries.
In the early 20th century, Russian jeweler Peter Carl Fabergé made 18K rose gold popular for imperial eggs, jewelry, and other decorative items. Today, rose gold is commonly used in jewelry, watches, and tech gadgets like phones and laptops. Jewelry manufacturers often market rose gold pieces as having a vintage look and feel. The use of pink gold remains highly popular in Russia.
Alloy Contents in Pink Gold
While copper is the main alloying metal that gives gold its pink tint, other metals are also used in some rose gold mixes. Here is an overview of common pink gold alloys and their composition:
|Alloy||Gold Content||Copper Content||Other Metals|
|14K rose gold||58.5%||41.5%||Silver, Zinc|
|18K rose gold||75%||22.25%||Silver, Zinc|
|22K rose gold||91.6%||4.95%||Silver, Zinc|
|24K pink gold||99%||1-2%||Copper|
As you can see, 14K and 18K rose gold contain a mix of gold, copper, silver, and zinc. The higher the gold content, the less copper is needed to achieve a pink hue. 22K rose gold only requires around 5% copper to take on a pink tone. 24K pink gold gets its subtle color from just 1-2% copper content.
How Copper Creates the Pink Color
Pure copper has a reddish-orange color. When it’s combined with the yellow gold alloy, the resulting mixture reflects a pinkish-red tone. Here’s a more in-depth look at why the copper causes this color change:
– Copper has a lower reflectivity than gold on the surface of the alloy. This absorption effect reduces the yellowish gold sheen.
– Copper atoms have aUnique arrangement and electron structure. This causes them to absorb blue and yellow wavelengths of light.
– With blue and yellow light absorbed, the dominant reflected light takes on a pink or red hue.
– Higher copper content results in more blue and yellow wavelength absorption, creating a deeper pink color.
– An alloy with 25% copper content will appear much pinker than 14% copper in rose gold.
So in summary, the pinkish color is created by copper’s atomic structure and how it absorbs particular wavelengths of light versus how gold reflects light. Alter the percentage of copper, and you change the intensity of the rose gold color.
How Other Metals Affect Color
While copper plays the biggest role in creating the pink or red color in rose gold, other metals can impact the final hue and clarity. Here’s an overview of how common alloying metals impact gold’s appearance:
– **Silver** – Silver is often used in rose gold rather than nickel, which can cause allergic reactions. When combined with copper, silver can subdue copper’s pink tones and create a softer, more golden rose color.
– **Zinc** – Zinc is added to rose gold alloys as a substitute for nickel. Zinc oxide forms on the surface as the alloy ages. This can make the color appear more vintage and muted over time.
– **Nickel** – Nickel is sometimes used instead of zinc or silver to strengthen gold. But it can cause allergic skin reactions with prolonged contact. Nickel gives the alloy a warmer, more yellow tone.
– **Palladium** – Palladium is a white precious metal occasionally used in rose gold. It helps maintain the pink color and provides a more durable alloy. But palladium is rare and costly.
While copper is the primary metal responsible for rose gold’s color, these secondary metals can alter the final look from a soft pink to a bold coppery-orange red tone. Jewelers will sometimes tweak alloy mixes to achieve a desired rose gold hue.
Rose Gold Plating and Fill
Rose gold plating and fill can give jewelry or items a pink gold finish at lower cost. Here is an explanation of each process:
– **Rose Gold Plating** – This involves applying a thin layer of 18K rose gold to a base metal surface via electroplating. The plating is usually less than 1 micron thick. With wear over time, the pink color may fade as the base metal shows through.
– **Rose Gold Filled** – This uses a thicker layer of gold bonded to a base metal core. Gold filled jewelry has at least 5% 18K rose gold applied to the base metal surface. Gold filled items are much more durable than plated rose gold.
Solid 14K or 18K rose gold alloy will be the highest quality and most durable. But rose gold plating and fill can provide a cost-effective alternative for achieving the pink gold look temporarily. Over time, the plating may need reapplied as it wears down.
Caring for Rose Gold Jewelry
Rose gold is relatively durable, especially at 18K and higher. But some care is required to maintain the integrity and pink color over time. Here are some rose gold jewelry care tips:
– Avoid prolonged exposure to chlorine, saltwater, chemicals, and abrasives. These can damage the pink color surface.
– Store rose gold separately from other jewelry to prevent surface scratches.
– Clean rose gold with mild soap, water, and a soft cloth. Avoid harsh jewelry cleaners.
– Arrange periodic professional cleanings for rose gold jewelry. This removes built-up dirt and oils.
– For rose gold plating or fill, be extra careful to avoid knocks, scrapes and prolonged wear that can reveal the base metal underneath.
With proper care and occasional cleaning, quality rose gold jewelry will maintain its pinkish color and luster for many years. Taking steps to protect it from damage will keep rose gold looking beautiful.
The pinkish-red color that distinguishes rose or pink gold comes from the copper content in the gold alloy. Copper has a reddish tone and absorbs blue and yellow light wavelengths, causing the reflected light to take on a rosy glow. Higher copper levels mean a deeper pink color. While copper is the primary factor, other metals like silver, zinc, and nickel also impact the final rose gold tone. The unique pinkish shine of rose gold adds beauty and elegance to jewelry, watches, and decorative items. With proper care, the blushing color lasts a lifetime.