Relative humidity (RH)

The amount of water vapour in air as a percentage of the maximum it can hold at that temperature. Collections aim for 40–55 % and stability; pyrite wants below 30–45 %; amber and some organics suffer below about 35 %.

Sources

SPNHC — Collection care resources
Collins, C. (ed.) (1995). The Care and Conservation of Palaeontological Material

Cite this article

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

BibTeX · CSL-JSON

@misc{stratum-rh,
  title        = {Relative humidity (RH)},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/glossary/rh}},
  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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