KISHUN AUCTION is a business-to-business auction specializing in colored gemstones and jewelry, serving buyers and sellers in Japan and overseas. Based in Okachimachi, Tokyo, it aims to redefine the value of pre-owned gems and build a marketplace connecting the local trade with global markets. Its auction categories include colored-stone jewelry and loose colored stones, diamond jewelry and loose diamonds, and pearls. Many offered pieces are reused items with added value from design, polishing, or grading and sorting, helping professional buyers assess their quality.

The auction combines online bidding with in-person, live bidding, giving participants the convenience of remote access and the opportunity to inspect items and compete at the venue. Sellers can reserve items for auction and receive support through the sale process, from consignment to payment. Buyers can use the bidding system and arrange to preview items in person. Participation requires registration, submission of specified documents, and review by the operator.