THE MAISON STANDARD
The Astrea Standard
≈1%
Among the finest 1% of diamonds, selected to our standard.
Astrea’s ambition is to work within approximately the top 1% of available diamonds, judged against our own standards. This is an internal selection benchmark, not an independent worldwide ranking. It combines colourless grades, VS clarity or better, excellent or ideal cut where graded, exceptional light performance, Hearts & Arrows precision where applicable, independent certification and a final human decision. Each stone is also individually checked by our gemologists, its report and specifications remain the definitive record.
Eight stages of discernment
From the loose stone to the signed jewel, quality guides every stage.
- 01
Stone
Diamond in every scientific sense
We begin with lab-grown diamonds: carbon crystals with the same chemical composition, crystal structure, optical properties, hardness and durability as mined diamonds. Origin differs; the material does not.
- 02
Selection
Grades narrow the field; the eye makes the choice
The selection benchmark begins in the colourless range and at VS clarity or better. Our gemmologists then examine each candidate for transparency, balance and character. A matching grade never guarantees a matching presence.
- 03
Cut & light
Proportion is judged by what the stone returns
Where a cut grade is issued, Astrea’s standard is Excellent or Ideal. We also assess brightness, fire, scintillation and the balance of light and shadow. Hearts & Arrows precision is considered where the shape and report support that assessment; it is not a universal grading category for every cut.
- 04
Certification
Independent facts, stone by stone
Qualifying centre stones are accompanied by an independent IGI or GIA grading report recording origin and the assessed characteristics. The report number can be checked directly with the issuing laboratory.
- 05
Design
The stone and silhouette are resolved together
Every silhouette is drawn with proportion, wearability and the movement of light in mind. The setting is not decoration around a stone; it determines how that stone sits, catches light and belongs on the body.
- 06
Setting
Placed and finished by hand
Setters seat each stone under magnification, cutting claws and refining galleries for security, alignment and light. Polishers then finish the surfaces and edges that determine how the jewel feels as closely as how it looks.
- 07
Hallmarking
Precious metal, independently assured
Astrea works in certified 18k gold and platinum 950. Pieces above statutory UK weight thresholds are independently tested and hallmarked; pieces below them follow Astrea’s documented due-diligence process.
- 08
Final inspection
A second pair of eyes
Before release, the finished piece is examined again by someone other than its maker. Stone security, alignment, articulation, polish, finish and hallmark are checked. Only then is the jewel signed off.
What you can verify
Evidence, not adjectives
For a particular stone, its laboratory report is the authority for origin and grade. Enter the report number directly with IGI or GIA. For the finished jewel, UK hallmarking independently verifies precious-metal fineness where legally required; Astrea’s Assay Assured registration is also publicly verifiable.
See the difference in daylight
Our gemmologists can compare stones, proportions and reports with you in person or by video.
Book an appointment