What is Pyrite?

Pyrite or Iron pyrite (FeS2) is a very common mineral that can be found in sedimentary and low grade metamorphic rocks in the form of crystals. It is often referred to as 'Foold Gold' due to it's gold-like colour.


Where is pyrite found in Ireland?

Pyrite is found most abundantly in North Leinster especially in North county Dublin, Louth, Meath and Offaly.


Why is Pyrite a problem?

The presence of pyrite in construction materials such as aggregates used in floor hardcore can lead to problems if exposed to certain conditions. Materials containing large amounts of pyrite are likely to expand, crack and crumble over time this is due to a chemical reaction that takes place when they are exposed to oxygen and moisture. This expansion can lead to cracks in walls and floors.


How is the problem of pyrite dealt with?

Pyrite remediation involves the removing of the floor hardcore that contains the pyrite and replacing it with pyrite free aggregate that meets new building standards.