NOBILITH Academy
Understanding gemstones
A reference library on formation, properties, origin, colour, inclusions, cut, treatments and laboratory examination. No course, no exam: look things up, understand them, place them in context.
Masterclasses
In-depth masterclasses on diamond, coloured diamonds, ruby, sapphire, emerald, alexandrite and Paraíba tourmaline – colour, character and documentation.
- Paraiba TourmalineA considered NOBILITH introduction to paraiba tourmaline: colour, character, documentation and individual selection.Read more
- AlexandriteA considered NOBILITH introduction to alexandrite: colour, character, documentation and individual selection.Read more
- EmeraldA considered NOBILITH introduction to emerald: colour, character, documentation and individual selection.Read more
- SapphireA considered NOBILITH introduction to sapphire: colour, character, documentation and individual selection.Read more
- RubyA considered NOBILITH introduction to ruby: colour, character, documentation and individual selection.Read more
- Coloured DiamondsA considered NOBILITH introduction to coloured diamonds: colour, character, documentation and individual selection.Read more
- DiamondA considered NOBILITH introduction to diamond: colour, character, documentation and individual selection.Read more
Knowledge
Articles on specific questions in gemmology: treatments, origin, durability and reading laboratory reports.
- How to read a gemstone dossierA dossier brings together everything that describes a stone – from the laboratory report to custody. Here is how to read it in the right order.Read more
- Natural, synthetic and imitation materialThree terms that are often confused: what they mean, how a laboratory tells them apart and why the classification must never rest on assumption.Read more
- Why colour changes under different lightThe same stone can look different in daylight than under a lamp. The reason lies in the interplay of light source, absorption and the eye.Read more
Gem Lab
Instruments and methods of gemmological examination.
- Gemmological microscopeThe most important instrument in the laboratory: under the microscope, inclusions, growth features and signs of treatment become visible.Read more
- RefractometerThe refractometer measures how strongly a stone bends light. This allows many materials to be narrowed down quickly – within clear limits.Read more
- PolariscopeBetween two crossed polarising filters a stone reveals how it refracts light. A simple instrument with meaningful results.Read more
Laboratory reports
How a laboratory report is structured and what each entry means.
- Understanding a laboratory reportA laboratory report is a gemstone's most important document. Which information it contains, how to read it and what it does not say.Read more
- IdentificationIdentification is the first and most important statement in a report: which material is this? Why every word in it counts.Read more
- Species and varietyRuby and sapphire are the same mineral, and so are emerald and aquamarine. What species and variety mean and why the boundary is sometimes debated.Read more
Glossary
Gemmology terms explained briefly and clearly – the reference section of the NOBILITH Academy.
- Absorption spectrumWhen light passes through a gemstone, the stone absorbs certain wavelengths – the rest make up its colour.Read more
- AfghanistanAfghanistan is an old source of ruby and emerald; both are mined in the mountains of the Hindu Kush.Read more
- AsterismAsterism is the star effect of certain gemstones: on a domed stone a four- or six-rayed star appears and glides across the surface as the stone moves.Read more