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In UK GEMINI 2.3, as well as restructuring the content, the following changes have been made:

  • There is one new element which is mandatory for datasets and series:
    • Spatial representation type (Note: this element was in GEMINI v1, but was removed from GEMINI v2)
  • The XML encodings for Use constraints & Limitations on public access have changed
  • There are several additional mandatory "metadata on metadata" elements, which were already required to encode the record:
    • File identifier
    • Hierarchy level name
    • Quality scope
  • There is one additional optional "metadata on metadata" elements: 
    • Parent identifier
  • There are two additional conditional elements:
    • Character encoding
    • Data quality
  • Four elements have been made mandatory
    • Conformity
    • Dataset language
    • Data format
    • Spatial reference system
  • Unique resource identifier renamed to Resource identifier
  • The element Maintenance information has replaced Frequency of update
  • Vertical extent information may now have multiple occurrence.
  • There are changes to the guidance for a lot elements, bringing in guidance relating to INSPIRE and
    • Title
    • Alternative title
    • Abstract
    • Keyword
    • Temporal extent
    • Vertical extent information
    • Spatial reference system
    • Spatial resolution
    • Resource locator
    • Data format
    • Responsible organisation
    • Limitations on public access
    • Additional information source
    • Metadata language
    • Resource identifier
    • Resource type
    • Conformity
    • Coupled resource
  • Dates (in both Temporal extent, and Dataset reference date) can no longer just be the century.

Editorial changes since the launch of GEMINI 2.3

March 2019

Change to, to describe a wider choice of relevant XML Schema Definition Files (XSDs) that can be used to validate GEMINI instances.

Dataset reference date: removed mention of the maximum occurence for service records, when viewing this element for dataset records.

Corrected the INSPIRE "corresponding element" entry for Conformity, Abstract, Topic category, Keyword, Spatial reference system, Data format, File Identifier, Hierarchy level name, and Quality scope.

Corrected the "corresponding element" entries for service elements to reference ISO 19119 for Extent, Vertical extent information, Spatial data service type, and Coupled resource.

Corrected the ISO 19139 "corresponding element" entries for service elements Extent, Vertical extent information, and Spatial resolution

Corrected the ISO 19139 "corresponding element" entries for Title, Alternative title, and Abstract.

Note: these are all minor corrections of the way the element is referenced, rather than substantive changes to which element we consider equivalent. The largest impact is to note that INSPIRE only allows one Quality scope element - i.e. the metadata has to describe the whole dataset.

January 2019

New Schematron package, in which the only change is to the "Technical Documentation" file (to version 1.7.1), clarifying in one paragraph that the Schematron file itself changed from 2.2 to 2.3, but the way one should use it didn't.

October 2018

Additional information (source) and Resource locator

Clarified that, in line with the underlying ISO standards, Resource locator is for links to access the resource, or obtain more information about accessing the resource. Links to further information about the resource itself, e.g. a user guide, should go in Additional information

Note: this is a change from the earlier UK Location guidance, which wanted all URLs (except licensing) in Resource locator.

The actual changes are in the 'purpose and meaning', guidance, and examples of both elements. Also noted that there is an INSPIRE element corresponding to Additional information, although it is only mentioned in an Annex of the Technical Guidance. We have also changed the name from 'Additional information source' to 'Additional information', because it is quite possible to provide the information in line, rather than by citation or link.

Note: additional information is not available for services.

Resource identifier

Fixed two typos.

We have also turned internal cross references from one element to another, into hyperlinks.

September 2018

Dataset language and metadata language

Corrected the name of the Irish language.

Spatial reference system and Quality scope

Corrected that there is an equivalent INSPIRE requirement, although not a 'named' metadata element.

Limitations on public access

Corrected the equivalent ISO 19115 & 19139 elements

Use constraints

Corrected encoding rules & examples, from "gmd:LegalConstraints" (which doesn't exist) to "gmd:MD_LegalConstraints".

Corrected the service Example One.

Corrected the equivalent ISO 19115 & 19139 elements.

August 2018

Description of validation

Fixed the description in section 1.5 of the Common Metadata Errors article, which only described the GEMINI 2.2 / UK Location / validation.

Parent identifier

Corrected to be slightly different guidance for service metadata.

Spatial data service type

Given that it is only relevant to service metadata, corrected the obligation (in that context) to mandatory

Minimum length of Abstract

Add mention in the guidance that the Schematron will complain if it's <100 characters


Fixed the reference - the list of INSPIRE CRSs is in Annex D.4 of the Metadata TG, not the Regulations

July 2018

UK GEMINI Encoding Guidance

first line: remove misleading phrase "using XSD schemas"

section 2.2.14: minor clarifications, and improved the placement of figure captions.

Change log (this article): reordered to bring newest to top; added this section (editorial changes)

"Home page": fixed link to encoding guidance

Guidelines - part 1 Introduction to Metadata: clarifications & general update

All pages: introduce a link back to the GEMINI 2.3 "home page".

Guidance for element 3 Dataset language: fix typo in anchor text for ISO 639 link

Guidance for element 44 Bounding box: fix typos in two domain sub element names


In UK GEMINI 2.2, the following changes were made:

  • The elements Frequency of update and Spatial reference system become optional;
  • For the elements Temporal extent, Spatial reference system, Spatial resolution, Unique resource identifier, Equivalent scale, multiple occurrences are allowed;
  • The elements West bounding longitude, East bounding longitude, North bounding latitude, South bounding latitude are merged to form Bounding Box for which multiple occurrences are allowed.


 Resource language, Metadata language:

  • The code for the Ulster Scots language was changed to "sco".

 Dataset reference date:

  • Occurrence changed to multiple
  • Data type changed to a class comprising the elements:
    • date
    • date type (publication/revision/creation)


  • Deletion of "by country or subdivision of country" from definition, with data type changed to character string and domain to an identifier.

Data format:

  • Data type changed to a class comprising the elements:
    • Name of format
    • Version of the format (date, number etc.)

Limitations on public access:

  • Equivalent ISO 19115 element changed from accessConstraint to otherConstraints, making domain free text.

Unique resource identifier:

  • Data type changed to class, comprising the elements:
    • code
    • codespace

Resource type:

  • Domain values changed dataset, series, service to match INSPIRE.

Conformity, Specification:

  • Combined into a new class Conformity, comprising the elements:
    • Specification
    • Degree
    • Explanation

Keyword, Originating controlled vocabulary:

  • Combined into new class Keyword, comprising the elements
    • keyword value
    • originating controlled vocabulary.

An optional element, Equivalent scale has been added.


The following elements were deleted:
  • Presentation type
  • Supply media
  • Spatial representation type
  • Browse graphic
  • Metadata standard name
  • Metadata standard version
None of these were mandatory, and they are all part of the larger ISO 19115 set. 
The following element names were changed:
  • Subject to Keyword
  • Online resource to Resource locator
  • Date to Temporal extent
  • West bounding coordinate to West bounding longitude
  • East bounding coordinate to East bounding longitude
  • North bounding coordinate to North bounding latitude
  • South bounding coordinate to South bounding latitude
  • Access constraints to Limitations on public access
  • Date of update of data to Metadata date
  • Distributor and Originator (merged) to Responsible organisation
The following elements were added to meet the requirements of INSPIRE:
  • Unique resource identifier
  • Resource type
  • Conformity
  • Equivalent scale
  • Metadata language
  • Metadata point of contact
  • Spatial data service type (for services)
  • Coupled resource (for services)
Other minor changes are identified in the element tables.

Last updated: August 2018

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