Identity
What the material is, whether it is natural, and whether further laboratory testing is appropriate.
Gemstone Sourcing
Selection is evidence, observation, and judgement.
A beautiful gemstone is only part of the decision. We also consider identification, known treatment, documentation, durability, and whether its price is supported by what can be seen and verified.
How We Assess
Six questions before a stone becomes a Caliste piece.
Colour
Hue, tone, saturation, distribution, and how the stone changes under different light sources.
Cut
Proportions, symmetry, windowing, extinction, polish, and whether recutting would improve or diminish the gem.
Clarity
The type, position, and visibility of inclusions—and what they mean for appearance and durability.
Treatment
Any known heating, filling, diffusion, coating, or other enhancement that should be disclosed.
Wearability
Hardness, toughness, setting risks, and whether the stone suits the client’s intended use.
Treatment & Certification
A certificate is important—but it is not a beauty report.
A gem laboratory can provide an independent opinion on identity and, where possible, treatment and geographic origin. It does not decide whether a stone is attractive, well cut, suitably priced, or right for a particular piece.
We read documentation alongside the stone itself. Where a report is available, we match its identifying details before sale and explain what its conclusions do—and do not—mean.
Questions to Ask
Before choosing a gemstone.
- Is the gemstone natural, synthetic, or assembled?
- What treatments are known or reasonably expected?
- Which claims are supported by an independent report?
- Are inclusions or the cut likely to affect durability?
- How should the stone be cleaned, stored, and serviced?
