The Process
Our method has been refined, but not fundamentally changed, since the firm was founded in 2014. Every stage is documented, photographed and archived in triplicate, indefinitely. The case file you receive is the case file we keep.
01
Items arrive by appointed insured courier. Each parcel is opened on camera by two staff members, never alone. Contents are photographed, weighed and dimensioned, and assigned a Xene case number that follows the item for life. Items are immediately placed in a controlled-environment intake safe pending examination.
02
Our research team consults hallmark registers, auction catalogues, dealer archives, museum records and where appropriate the Art Loss Register. Prior owners, sale records, exhibition history and any prior certifications are documented in the case file. Suspicious provenance is flagged before any examination begins.
03
Comparative analysis under controlled lighting at up to 200×, including raking, axial and ultraviolet examination. Where appropriate, XRF spectroscopy confirms metallurgical composition. Suspected restoration is examined under raking light at low angle. Two senior specialists must independently authenticate before grading proceeds.
04
Two senior specialists in the relevant discipline grade independently, recording strike, lustre, eye-appeal, centring, gum, freshness or condition factors as appropriate in a sealed digital form. Neither specialist sees the other's grade. A third — the finaliser — reconciles disagreements. The final grade is unanimous, or it is not awarded.
05
The item is sealed in an inert, UV-stable acrylic holder cut to its dimensions on a precision CNC at our atelier in Surrey. A discreet security mark, an NFC tag and a laser-engraved certificate number are embedded in the rim. The seal is sonically welded; opening the holder is mechanically destructive and immediately visible.
06
A hand-signed paper certificate is issued by both grading specialists and the head of department. A digital twin is published in our public registry, accessible by tapping the holder's NFC tag. Every Xene certificate carries a lifetime guarantee of authenticity, underwritten by Lloyd's of London under policy LM/2024/8841.
07
Items are returned by the courier of your choice, with full insured coverage and discreet, unmarked packaging. International shipments are handled by our partners in London, Geneva, New York, Hong Kong and Dubai. For items above £500,000, armoured carrier is included as standard.
Instrumentation
We invest in instrumentation as we would in our specialists. Calibration logs, service records and reference standards are audited annually by an independent metrologist.
Stereo microscope
Leica M205C, 1.6×–160×, with apochromatic objectives and calibrated illumination.
XRF spectrometer
Bruker Tracer 5g handheld, calibrated weekly against NIST reference standards.
Ultraviolet examination
Long-wave (365nm) and short-wave (254nm) inspection in a blackout chamber.
Precision balance
Sartorius Cubis MCA225P, readability 0.01mg, with daily calibration log.
Digital calliper
Mitutoyo absolute Digimatic, 0.001mm resolution, paired to case file directly.
Specimen photography
Profoto Pro-11 with Schneider apo-component lenses; raw plates archived in triplicate.
Chain of Custody
Day 0
Submission opened by client in our portal; courier instructions issued.
Day 2
Parcel arrives at Hatton Garden. Two-person opening and intake.
Day 5
Provenance review complete; authentication examination begins.
Day 14
Dual-blind grading complete; finaliser reconciliation in progress.
Day 28
Encapsulation, certification and registry entry. Insured return shipping.
The Certificate
Every Xene certificate is hand-printed in our London studio on 350 gsm Hahnemühle cotton paper, gold-foil stamped and blind- embossed with the house seal. It is signed by the two grading specialists and countersigned by the head of department.
Guarantee
Every Xene certificate carries a lifetime guarantee of authenticity. Should any item we have certified be subsequently proven inauthentic, Xene undertakes to compensate the bearer at the prevailing market value.
The guarantee is underwritten by Lloyd's of London under policy LM/2024/8841. It is transferable, indefinite, and printed on the certificate itself. The guarantee survives the firm; it is backstopped by an irrevocable trust held with Coutts.
Discuss your collectionAtelier
Every specialist works from a Xene bench, fitted with our own tools, calibrated to the same standard. The result is a grade you can trust to mean the same thing today as in a decade's time.
