Gold Jewelry Glossary | Karats, Colors, and Gold Types Explained

Gold is one of the most iconic and cherished materials in jewelry. But not all gold is created equal. This glossary covers everything you need to know about gold — including karat levels, color variations, finishing techniques, and sourcing terminology — to help you make informed decisions when choosing fine jewelry.

What is Gold?

Gold is a naturally occurring precious metal known for its softness, warmth, and resistance to tarnish. It has been used for millennia in decorative arts and jewelry. In its pure form (24 karats), gold is soft and malleable, making it necessary to alloy it with other metals for greater strength and durability in jewelry.

Understanding Karats (Karat Purity in Gold Jewelry)

Karat (abbreviated as K or kt) is a unit of measurement that indicates the proportion of pure gold in an alloy.

24K Gold

• Composed of 99.9% pure gold
• Bright yellow in color
• Very soft and not suitable for most jewelry
• Commonly used in certain cultural or ceremonial pieces

18K Gold

• Composed of 75% pure gold and 25% alloy metals
• Rich, warm golden hue
• Slightly softer than 14K but highly desirable for fine jewelry

14K Gold

• Composed of 58.3% pure gold and 41.7% alloy metals
• More durable and scratch-resistant than 18K
• Widely used for everyday jewelry

Gold Colors in Jewelry

Different metal alloys are mixed with gold to produce a variety of colors, each with its own aesthetic and wear characteristics.

Yellow Gold

• Mixed with copper and silver to maintain a classic golden tone
• Timeless and often associated with traditional styles

White Gold

• Created by alloying gold with white metals like palladium or nickel
• Often plated with rhodium for enhanced brightness and scratch resistance
• Offers a modern, neutral tone

Rose Gold

• Made by mixing gold with copper
• Features a pink or reddish hue
• Known for its romantic and vintage appeal

Gold Vermeil

Gold vermeil is a high-quality jewelry finish that consists of a thick layer of gold plated over a base of sterling silver. For jewelry to be classified as vermeil, it must meet specific criteria:

• Gold layer must be at least 10K in purity
• Thickness must be at least 2.5 microns
• Base metal must be sterling silver (not brass or other metals)

Vermeil is a premium alternative to traditional gold plating, offering better durability and value.

Gold-Plated vs. Gold-Filled Jewelry

Gold jewelry is often made using different techniques to apply gold to a base metal.

Gold-Plated

• Involves applying a very thin layer of gold (often less than 0.5 microns) over a non-precious base metal
• Least durable of gold types
• Can wear off over time, especially with frequent contact or moisture

Gold-Filled

• Features a thick layer of real gold (usually 14K) mechanically bonded to a base metal
• The gold layer is significantly thicker than in gold-plated jewelry
• More resistant to tarnish and fading; suitable for frequent wear

Ethical & Recycled Gold

Ethical gold refers to gold that is sourced in a responsible and transparent way, with minimal environmental impact and no ties to conflict zones. Recycled gold is refined from existing jewelry, industrial sources, or scrap, and is chemically identical to newly mined gold.

Benefits of recycled and ethically sourced gold:

• Reduces demand for destructive mining
• Supports sustainable practices
• Maintains the same quality and purity as virgin gold

Gold Hallmarks

A hallmark is a stamped marking found on gold jewelry that certifies its purity and authenticity. Common hallmarks include:

• “24K”, “18K”, or “14K” – Indicating karat purity
• “585”, “750”, or “999” – Numeric equivalents used internationally
• Additional marks may indicate the country of origin, manufacturer, or certification body

Hallmarks are an important assurance of quality and are required by law in many countries.