{
  "id": "urn:example:observation:42",
  "metric": {
    "value": "mass",
    "scheme": "https://example.org/metrics/v1"
  },
  "quantity": {
    "value": "12.75",
    "unitCode": "KGM",
    "unitScheme": "https://unece.org/code-list-recommendations"
  },
  "observedAt": "2026-09-08T08:00:00Z"
}