KOS is a sub-brand of CELI Jewelry, a family business brand that has been dealing with natural diamond and natural gemstone for over 50 years, established in 1975. Our experienced GIA-certified gemologists source and select only the best quality diamonds. We have over 500 laboratory-grown diamonds for you to choose from at our flagship store, covering all shapes, sizes, and quality grades.

We also have our own in-house production facility. Every piece of jewelry is made by the hands of experienced craftsmen who have accumulated expertise and meticulousness over decades from generation to generation. Every piece of jewelry must pass strict quality control before it reach to your hands.