Miseki Jewelry has been in business since 1967, with over 52 years of commitment to quality, value, and integrity.


pearl jewelry
diamond jewelry
wedding bands
Swarovski crystal 
Colored stones jewelry
watch battery replacement

We also carry.....

Seiko watch 
(Miseki Jewelry is authorized exclusive dealer for Seiko Watch in Northern California.)
Citizen watch

We are graduated from Gemological Institute of America
-applied jewelry professional

Masaharu Mike Nagasuga

owner, gemologist, appraiser

He graduated from Gemological Institute of America (GIA) in 1980. He has the comprehensive knowledge of diamonds and colored stones, technical expertise and practical skills to evaluate gemstones by the 4Cs (color, clarity, cut, and carat weight), the International Diamond Grading System™, and the Colored Stone Grading System. 

He does

  • Develop in-depth, hands-on experience with the GIA International Diamond Grading System™ and the 4Cs (color, clarity, cut and carat weight)

  • Grade diamonds in the D-to-Z color range

  • Build a knowledge base about colored stones and the colored stone market

  • Use gemological equipment effectively to identify gemstones

  • Use the GIA Colored Stone Grading System to evaluate gemstone quality

  • Identify gemstone characteristics, simulants and treatments, and recognize when advanced testing is required

  • Understand how gems are mined, fashioned and brought to the marketplace

  • Recognize how quality, rarity and color affect value

  • Determine how market factors affect gem value

He is also honest, and takes pride in selling fine products. 

Miseki Jewelry has been a long-time supporter of the Queen Program Committee and always presented the 1st place winner with a prize necklace every year since the program’s beginning. The certificate of appreciation was sent to him by the City and County of San Francisco for his generosity and commitment to the Japanese American community. 

GG certificate
certificate of appreciation.jpg

We are in the ANA Mileage Club (AMC) Partners Program