Jewelry Miura Co.


The answer is ... it is an alloy of gold and aluminum with other minerals.

It has been known for 5 decades that the addition of aluminum to 24K pure gold could result in purple gold.
The reason why it took so long to develop purple gold as a commercially viable product is because of problems with discoloration, toughness and durability.
There are various processes involved in the commercialization of purple gold.
After many years of research and testing, the time for producing and wearing beautiful purple gold jewelry has arrived.

>>You can find more information on wikipedia about purple gold.

Cierin is a unique brand of purple gold jewelry.
The brand was born in Japan in 2009.
The name "Cierin" comes from the Japanese word "紫凛".
"紫-cie" in Japanese means purple.
Purple color symbolizes nobility, spirituality, and elegance since the Nara period (710-794).
In Western psychology, it symbolizes change and healing.
"凛-rin" in Japanese, we symbolize it as beauty filled with spirit.
Cierin was created for those who challenge the changing times.


In addition to our finished product like Cierin,
we also accept custom-made products by OEM.
Would you like to make a product using purple gold
that has never been made before?
Due to the special material, it used to take time to remold molds,
but our new manufacturing method allows us to remold molds in a short time.


We are a Tokyo-based jewelry manufacturer in business for 42 years.
We have been making jewelry using purple gold, which is difficult to commercialize in Japan, for over 10 years.
We are looking for retailers who can handle "Cierin" and companies who can do custom-made OEM. Please feel free to contact us.

Jewelry Miura Co.

Our office will be relocated as of the end of July 2022.

Until the end of July 2022.
JTT Bld.6F & 7F, 3-3-4, Ueno, Taito, Tokyo, 110-0005, Japan
From August 2022.
U&M Bld.2F, 1-14-5, Higashiueno, Taito, Tokyo, 110-0015, Japan
Fumitsugu Miura

18K Purple Gold has passed a gold purity analysis for the first time conducted by the Japanese Mint, which manufactures Japan's coins. Purple Gold was graded with the "Hallmark" designation as a proof of its gold purity from January 2022.
The hallmark design is indicated by the Japanese flag, which indicates that it is a proof of the Japan Mint, the Hinomaru, and the number in the diamond that indicates the grade (purity) in parts per thousand.
In the case of K18, the mint symbol is a combination of the Japanese flag and a diamond shape that indicates that the gold grade is 750 (18K gold ).

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