Inclusion Fingerprinting
Definition
Identification of mineral inclusions trapped inside a gemstone during growth as indicators of the geological environment. Marble-hosted rubies typically contain calcite and dolomite inclusions; skarn rubies contain grossular garnet and diaspore. Inclusions are a complementary tool alongside isotope work.
- Basis
- Mineral inclusions trapped during crystal growth
- Marble-hosted ruby
- Calcite, dolomite inclusions
- Skarn ruby
- Grossular garnet, diaspore inclusions
- Role
- Complementary to isotope analysis
Common questions
Why can inclusion fingerprinting alone be insufficient to prove origin?+
Different deposits can produce visually similar inclusion suites, and some inclusions are ambiguous or absent in a given stone, so examiners pair inclusion evidence with isotope or trace-element analysis for a more defensible provenance conclusion.
How does treating or heating a gemstone affect inclusion fingerprinting?+
Heat treatment commonly used to improve colour or clarity can alter, dissolve, or fracture natural inclusions, which can destroy the diagnostic evidence needed to identify the deposit of origin.
Related terms
- Conflict Mineral
- A mineral whose extraction or trade finances armed conflict. The OECD defines 3TG (tin, tantalum, tungsten, gold) from conflict-affected and high-risk areas...
- Epsilon-Nd (εNd)
- The 143Nd/144Nd ratio of a sample expressed as a deviation in parts per ten thousand from the chondritic uniform reservoir (CHUR). Positive...
- Kimberley Process (KPCS)
- An international certification scheme launched in 2003 that requires participant countries to certify that rough diamonds are conflict-free before export. Isotope and...
- LA-ICP-MS Trace-Element Profiling
- Laser ablation inductively coupled plasma mass spectrometry applied directly to a polished gemstone surface. It measures dozens of trace elements simultaneously in...
- REE Pattern (Rare Earth Element Pattern)
- A plot of rare earth element concentrations normalised to chondrite or primitive mantle, showing the relative enrichment or depletion of each REE...