Inclusion

Any foreign body enclosed in a mineral, gem or resin: an insect in amber, a fluid bubble in quartz, a rutile needle in ruby. In amber the inclusion is the value; in gemstones it is usually a flaw and sometimes a signature.

Sources

Gemological Institute of America — Gem encyclopedia and glossary
Mindat — Mineralogical glossary (link only)

Cite this article

Stratum Study. "Inclusion" (Glossary). Stratum Study pack 2026.09, as of 2026-09-16. https://stratum.black/study/glossary/inclusion. Accessed 2026-09-20.

BibTeX · CSL-JSON

@misc{stratum-inclusion,
  title        = {Inclusion},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/glossary/inclusion}},
  year         = {2026},
  note         = {Glossary article, Stratum Study pack 2026.09, as of 2026-09-16; sources: stratum. Accessed 2026-09-20.}
}

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