What K is 100% Gold?

24k gold is 100% gold.

Understanding Gold Purity: The Karat System

Gold purity is measured using the karat system, which indicates the proportion of pure gold out of 24 parts. The reference clearly states that the purest form of gold is 24k gold.

According to the provided information:

• 24k gold refers to 100% pure gold.
• It is pure gold and contains no alloys (other metals).

This means that when a piece is described as 24 karat, it is composed entirely of gold without any other metals mixed in.

Characteristics and Use of 24k Gold

Because it is 100% pure, 24k gold has specific characteristics:

• Color: It is described as being "extremely yellow in color."
• Hardness: Due to its purity, 24k gold is very soft and malleable. This makes it less durable than gold alloys.

The reference notes that "this type of gold karat does not tend to be used for jewelry" in many parts of the world, especially for items that need to withstand wear and tear, precisely because of its softness. It might be used for investment (bullion coins or bars) or in specific cultural contexts where its extreme purity is valued, often for ceremonial items or very delicate pieces.

How Other Karats Relate to 24k

All other gold karats represent a percentage of pure gold mixed with other metals (alloys) like copper, silver, zinc, or nickel. These alloys are added to increase the gold's durability, change its color (e.g., to white gold or rose gold), and reduce its cost.

The purity of other karats is calculated based on 24k being 100%:

• 18k gold: 18 parts gold out of 24 = (18/24) * 100% = 75% pure gold
• 14k gold: 14 parts gold out of 24 = (14/24) * 100% ≈ 58.3% pure gold
• 10k gold: 10 parts gold out of 24 = (10/24) * 100% ≈ 41.7% pure gold

Here is a simple table illustrating the common karats and their approximate purity:

In summary, when the question is "What K is 100% gold?", the definitive answer, based on the standard karat system and supported by the reference, is 24 karat (24k).