The House
Born from obsession
House of Yusei was founded on a single conviction: that the rarest stones in the world deserve settings worthy of them.
Our story
A different kind of jeweller
House of Yusei was founded in 1967 by Kasutero Marubashi — a Japanese entrepreneur who brought his family to the United States to build a new life, and chose to build it around stones. What began as a single cutting bench in a rented workshop became, over six decades, one of the few jewellery houses in the world with direct ownership of its supply chain from the ground up.
The house operates two small diamond mines in India, giving us access to natural stones before they reach the open market — and the ability to trace every diamond we set back to the exact seam it came from. In Maryland, our lab-grown diamond facility produces exceptional stones under controlled conditions, held to the same grading standards as our naturals. We make no distinction in craft between the two: both deserve the same setting, the same attention, the same hands.
Our third speciality is exotic opals — sourced directly from fields in Australia and Ethiopia, chosen one by one for their play-of-colour. No two are alike. That is the point. The name Yusei means 'gentle star' in Japanese, and it is the quality we look for in every stone we bring into the studio: something quiet, something rare, something that rewards a second look.
From the source
We own what we sell
Most jewellers buy from wholesalers. We go further back. Our supply chain begins at the mine.
Two diamond mines
Our two mines in India give us direct access to natural diamonds before they reach the open market. Every stone is traceable to the seam it came from.
Lab-grown diamond facility
Our Maryland facility produces lab-grown diamonds held to the same grading standards as our naturals. The process is different. The standard is identical.
Exotic opals
We source directly from opal fields, selecting each stone individually for its play-of-colour. Crystal, boulder, and black opals — chosen one by one, never by lot.
Philosophy
What we believe
Stone first
We never design a setting before we have the stone. The stone dictates the form — its proportions, its light, its personality. The metal is in service of the gem.
Nothing hidden
Every piece leaves our studio with full documentation: stone origin, cut specifications, treatment history, and care instructions. Transparency is not a feature — it is the baseline.
Slow by design
We accept a limited number of commissions each season. Not because we cannot work faster, but because we will not. Exceptional work requires time, and time is what we give it.
Worn for generations
We build in platinum and 18ct gold because we are making heirlooms, not accessories. Every joint is hand-finished. Every prong is set to last a hundred years.
Craftsmanship
Made entirely by hand
Our studio produces no more than eighty pieces per year. Each one is conceived, modelled, cast, and finished by a single maker — so that every decision, from the angle of a prong to the polish of a gallery, is made with full attention. There is no production line. There is no compromise.
Begin a conversation
Whether you have a stone in mind, a feeling you cannot yet name, or simply a curiosity — we would love to hear from you.