Vivianite

Environmental Archaeology, A Guide to the Theory and Practice of Methods, from Sampling and Recovery to Post-excavation (second edition), published by English Heritage (now Historic England) in 2011, defines vivianite as: ‘hydrated iron phosphate; it produces a bright blue deposit, typically in waterlogged anoxic conditions; darkens rapidly upon oxidation.’

Geoarchaeology, Using Earth Sciences to Understand the Archaeological Record, published by Historic England in 2015, defines vivianite as: ‘an iron phosphate mineral Fe3(PO4)2.8H2O that crystallises in reduced, biologically rich environments. On exposure to air, it can turn to a strikingly blue powder.’

[edit] Related articles on Designing Buildings Wiki

• Agglomeration.
• Aggregate.
• Alluvium.
• Archaeology and construction.
• Archaeology.
• Building archaeology and conservation.
• Building archaeology.
• Colluvium.
• English Heritage.
• Historic England.
• Surface remains.
• Types of soil.