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The difference between K10 and K18 materials


What is the "K" in K10 and K18?

Symbols like K10 and K18 are often seen in jewelry shops and magazines. cobaco also handles jewelry made of K10 and K18.

What does the "K" represent? It actually stands for "karat," a unit that indicates the purity of gold. It shows how much gold is present in the jewelry.

By the way, the unit used to measure the mass of gemstones like diamonds is "carat," with the initial letter being "C," which is a completely different unit, so please be careful.

The gold content is 75% in K18, 58% in K14, and 41.7% in K10. K24 represents 100% gold, which means "pure gold."

Gold is a very delicate and soft metal. While it is a harder metal compared to platinum and silver, it is difficult to make jewelry directly from K24 (pure gold).

Jewelry that is prone to deformation cannot be used for everyday wear. Therefore, other substances are mixed to increase strength. There is no specific rule on what to mix with gold.

Although it varies by company, silver and copper are commonly mixed. When creating pink gold, more copper is added to adjust the color.


The difference between K10 and K18 that you think you know


Differences in color and strength between K10 and K18

K10 and K18. It's not about which one is better, but each has its own characteristics.

K10 is stronger and less prone to deformation and scratches compared to K18. However, it is not very resistant to impact due to its hardness. It is also weak to acids and prone to discoloration if not cleaned regularly. Especially pink gold is prone to discoloration, so some caution is needed. However, with polishing, the shine can be restored, and since the price is reasonable, it is easy for jewelry beginners to incorporate.

K18 is less prone to discoloration than K10, and its shine differs from K10. It is also said to be less likely to cause allergic reactions compared to K10, so those with allergies may feel more comfortable wearing K18 (note that not everyone is free from allergic reactions). However, being softer than K10, extra care is needed when handling delicate items like thin necklace chains. The softness also means it has flexibility, making it less prone to breakage from impacts. For those who wear jewelry for long periods during the day, K18 may be more suitable.

The difference between K10 and K18 that you think you know|cobaco

By the way, cobaco also offers a material called "K18 Hard," which is less prone to bending. If you are interested, please visitthis page.


Different gold hues depending on the store

By the way, are the color tones the same for K10 and K18? In fact, compared to K18, K10 has a slightly stronger pink hue in pink gold and a softer, lighter color in yellow gold.

This is yellow gold.

This is pink gold.


Furthermore, with K18 Hard, both pink gold and yellow gold have a lighter hue compared to regular K18.

Left is yellow gold, right is pink gold.


The color tones may vary slightly depending on the store.
At our store, we adjust the color composition to match the design of the jewelry. Please consider it as a rough guide rather than an exact color description.

It may be best to use each type based on personal preference, compatibility with the jewelry design, and the occasion. With proper care, both can be used for a long time.