Gemstone Identification — non-destructive testing to confirm species, detect treatments and assess origin indicators.
Diamond Grading. 4Cs evaluation with master stones, clarity plotting and fluorescence assessment.
Valuation for Insurance independent, defensible appraisal reports aligned with international standards.
Provenance & Due Diligence evidence review to support lawful trade, collection care and estates.
Sarah Ravenhill provides certified, independent gemological opinion for private clients, family offices and legal professionals. The practice delivers impartial identification, grading and valuation of diamonds and coloured stones with institutional rigour and absolute discretion.
Species confirmation, treatment detection and origin indicators using advanced microscopy and spectroscopy.
Independent 4Cs grading with diamond-specific instrumentation and master stone sets.
Formal, defensible valuations for insurance, estate and lending purposes.
All examinations are carried out using a documented, repeatable process. Photomicrography, refractive index, specific gravity, UV response and spectral features are recorded as appropriate. Opinions are issued only when evidence is sufficient to support them.
Determination of species and variety, assessment of enhancements and discussion of possible origin based on observed indicators.
Independent grading covering colour, clarity, cut and carat weight, including fluorescence and proportion analysis.
Independent value opinions for insurance scheduling, estates, collateral and equitable distribution.
Engagements are by appointment. All matters are handled with strict confidentiality and documentation is issued to institutional standards.
By appointment only
enquiries@sarahravenhill.com