On 13 October 2026, the TDWG Executive Committee ratified the new mineralogy extension terms as part of Darwin Core, the most widely used standard for sharing biodiversity and natural history collection data. For the first time, minerals, rocks and other geological specimens can be described with dedicated terms in the same standard that museums and data portals such as GBIF already use.
The update adds a new class, GeologicalMaterial, and 26 new properties, plus nine IRI-valued equivalents for linking to controlled vocabularies. With these, collections can record:
- compound specimens and their parts
- mineral and rock names and classifications
- measured chemical composition
- geological context beyond stratigraphy
- hazards and conservation needs
The terms were developed by the TDWG Mineralogy Extension Task Group. Eleven earth science collection specialists reviewed them, and they were implemented end to end on the GeoSpecimens platform before being proposed for Darwin Core.
The Task Group has also published a vocabulary of 17 Geological Material Assertion Types for mineral properties such as crystal habit, luster and cleavage. This vocabulary is not yet part of the standard and may be proposed in a future review.
The ratification is an important step towards making geological collection data easier to find and combine across institutions and portals, including GeoCASe and geoloogia.info.
Original announcement: https://www.tdwg.org/news/2026/mineralogy-extension-terms-ratified/
