Does Yellow Gold Tarnish?
by Werneri Grundström
·6 minutes
Yellow gold, a symbol of wealth and beauty for millennia, continues to captivate jewelry enthusiasts worldwide. But does this precious metal stand the test of time without losing its luster? Let's delve into the science, history, and care of yellow gold to answer this burning question.
More Gold, Less Tarnish
Yellow gold tarnish resistance depends on its purity:
- Pure gold (24k): Never tarnishes
- High karat gold (18k-22k): Highly resistant to tarnish
- Medium karat gold (14k-17k): Occasional slight tarnishing possible
- Low karat gold (10k-13k): More prone to tarnishing
Tarnish on gold alloys is typically surface-level and removable. Regular cleaning and proper storage prevent most tarnishing issues. Higher karat gold jewelry requires less maintenance to maintain its luster.
The Nature of Yellow Gold
Yellow gold is more than just a beautiful metal; it's a carefully crafted alloy:
- Pure gold (24k) is the base of all gold jewelry
- Alloys typically contain silver, copper, and sometimes zinc
- The ratio of these metals determines the gold's karat and color
Yellow gold derives its warm hue from the high percentage of pure gold, with subtle variations depending on the specific alloy composition. The science behind gold's color lies in its atomic structure, which absorbs blue light and reflects yellow and red wavelengths.
The Chemistry of Tarnish
Tarnish is essentially a chemical reaction between a metal and non-metal, typically oxygen or sulfur. Here's why pure gold doesn't tarnish:
- Gold has a filled electron shell, making it highly unreactive
- It doesn't readily form oxides or sulfides at normal temperatures
- Gold's electrode potential is positive, resisting corrosion
However, the other metals in gold alloys can react with the environment, potentially affecting the jewelry's surface over time.
Karat Grades and Tarnish Resistance
The karat system indicates gold purity, which directly correlates to tarnish resistance:
- 24k (100% gold): Virtually tarnish-proof but too soft for most jewelry
- 22k (91.7% gold): Extremely tarnish-resistant, suitable for special pieces
- 18k (75% gold): Highly tarnish-resistant, balancing durability and purity
- 14k (58.3% gold): Good tarnish resistance, popular for everyday wear
- 9k (37.5% gold): More prone to tarnishing, but still resistant compared to non-gold metals
For a deeper understanding of gold purity, explore our guide to gold jewelry stamps.
Environmental Factors Affecting Gold Jewelry
While pure gold remains stable, various external elements can impact gold alloys used in jewelry. Understanding these factors is crucial for maintaining your precious pieces and ensuring their longevity.
Chemical Exposure
Chlorine, ubiquitous in swimming pools and many household cleaners, poses a significant threat to gold jewelry. When exposed to chlorinated water:
- Copper in gold alloys may react, causing discoloration and a phenomenon known as "dezincification"
- Prolonged exposure can lead to structural weakening, particularly in areas where the metal is thinner
- In severe cases, chlorine exposure can cause stress corrosion cracking in gold alloys
Sulfur, present in air pollution, some foods, and even rubber bands, can tarnish the silver content in gold alloys:
- It forms silver sulfide on the surface, dulling the jewelry's luster
- This reaction is more pronounced in lower karat gold due to higher silver content
- While not permanent, sulfur tarnish can be unsightly and require professional cleaning
Cleaning Products
Harsh chemicals in everyday cleaners can damage gold jewelry, particularly lower karat pieces:
- Alkaline solutions can cause surface etching, diminishing shine and smooth texture
- Acidic cleaners may dissolve some of the base metals in the alloy, weakening the overall structure
- Ammonia, often found in household cleaners, can discolor gold and damage certain gemstone settings
Opt for pH-neutral, jewelry-specific cleaners to safely maintain your gold pieces. For more on proper cleaning techniques, visit our gold cleaning guide.
Physical Wear and Tear
Gold, especially in higher karats, is susceptible to physical damage due to its softness:
- Abrasive surfaces can cause micro-scratches, dulling the finish over time
- Impacts may deform softer gold pieces due to the metal's malleability
- Constant friction, such as rubbing against clothing or other jewelry, can gradually thin gold plating
To minimize wear:
- Consider removing gold jewelry during strenuous activities or when working with abrasive materials
- Rotate your jewelry wear to distribute wear evenly
- Store pieces separately to prevent scratching between items
Biological Interactions
Our bodies' natural chemistry can affect gold jewelry in surprising ways:
- Sweat and skin oils may leave residues, attracting dirt and dulling shine
- The pH level of an individual's skin can interact differently with gold alloys
- Some medications or dietary habits can alter body chemistry, potentially accelerating tarnishing
Interestingly, some people may notice their gold jewelry losing luster faster than others due to these biological factors. This is why a piece might tarnish quickly on one person but remain pristine on another.
Environmental Conditions
The environment in which gold jewelry is stored or worn can also impact its condition:
- High humidity can accelerate tarnishing, especially in coastal areas
- Extreme temperature fluctuations can cause metal fatigue over time
- Exposure to direct sunlight for prolonged periods can fade certain gold alloys
Protecting Your Gold Jewelry
To safeguard your gold pieces:
- Remove jewelry before swimming, cleaning, or applying beauty products
- Store items in soft, dry environments when not in use, preferably in individual cloth pouches
- Perform regular, gentle cleaning with appropriate products
- Consider professional cleaning and inspection annually for valuable pieces
- Use jewelry rolls or padded boxes when traveling to prevent damage
- Be mindful of your jewelry when engaging in activities that might expose it to harsh conditions
By understanding these environmental factors and taking proactive care measures, you can ensure your gold jewelry remains beautiful and lustrous for generations to come. Remember, different karat grades may require slightly different care approaches, so always consider the specific composition of your gold jewelry when developing a care routine.
Evidence: Ancient Gold Artifacts in Pristine Condition
The exceptional durability of gold is powerfully demonstrated by numerous ancient artifacts that have survived millennia in remarkable condition. These historical treasures not only provide insights into past civilizations but also serve as testament to gold's resistance to tarnish and corrosion.
Tutankhamun's Death Mask (14th century BCE)
One of the most famous examples of gold's longevity is the death mask of the Egyptian pharaoh Tutankhamun:
- Crafted around 1323 BCE from 22.5-karat gold
- Discovered in 1925 by Howard Carter, over 3,000 years after its creation
- The mask retains its original luster and intricate details
- Minimal signs of tarnish or corrosion despite millennia in a tomb
The mask's pristine condition highlights gold's ability to withstand the test of time, even when subjected to burial conditions.
The Cheapside Hoard (16th-17th century CE)
This remarkable collection of Elizabethan and Jacobean jewelry provides further evidence of gold's durability:
- Buried around the time of the English Civil War (mid-17th century)
- Discovered in 1912, having been hidden for approximately 300 years
- Gold items in the hoard emerged in excellent condition
- Includes delicate gold chains and settings that maintained their structure
The Cheapside Hoard demonstrates gold's resistance to underground conditions over centuries.
The Gold Lyre of Ur (c. 2500 BCE)
Perhaps one of the most striking examples of gold's longevity is the Gold Lyre of Ur:
- Excavated from the Royal Cemetery of Ur in modern-day Iraq
- Dates back to approximately 2500 BCE
- Features gold decorations that remain untarnished after 4,500 years
- Survived burial, climate changes, and eventual excavation
This ancient musical instrument showcases gold's ability to maintain its appearance across millennia, even when exposed to varying environmental conditions.
The Varna Gold Treasure (4600-4200 BCE)
Discovered in Bulgaria, this Neolithic treasure is one of the oldest known gold hoards:
- Dates back to 4600-4200 BCE
- Includes over 3,000 gold artifacts weighing over 6 kg in total
- Despite being over 6,000 years old, the gold items retain their shape and luster
- Provides evidence of advanced goldsmithing techniques in prehistoric times
The Varna treasure demonstrates that even the earliest worked gold can survive for millennia without significant degradation.
The Broighter Hoard (1st century BCE)
Found in Northern Ireland, this collection of Iron Age gold artifacts includes:
- A gold boat, torc, and other ornaments
- Dated to the 1st century BCE
- Despite being buried in waterlogged soil for over 2,000 years, the gold remains in excellent condition
- The intricate details of the craftsmanship are still clearly visible
This hoard showcases gold's resistance to even challenging burial environments, including moisture and acidic soil.
These examples from diverse cultures and time periods demonstrate gold's remarkable resistance to corrosion and tarnishing over thousands of years. Whether buried underground, hidden in tombs, or subjected to changing environmental conditions, gold artifacts have emerged from the depths of history with their beauty largely intact.
Conclusion
Yellow gold, in its purest form, does not tarnish. While gold alloys used in jewelry may experience some surface changes over time due to the presence of other metals, proper care and understanding of gold's properties can ensure your pieces remain beautiful for generations.
The enduring allure of gold, evidenced by ancient artifacts that have stood the test of time, underscores its unique place in human history and adornment. Whether you're drawn to the rich cultural significance of gold or its scientific properties, yellow gold jewelry remains a timeless choice.