Quantification of Pyrite in Roof Slates - Test Method
Determination of pyrite (FeS2) in roof slates
Tiles made of natural slate have been used extensively throughout the UK. They offer a relatively light, impermeable roof covering, that readily sheds water with a very traditional appearance. Roofing slates come in a wide range of colours that are mainly blues, greys, blacks and greens. The colour and texture is a reflection of the natural origin of the slate and varies from deposit to deposit and also within individual quarries. Similarly the quality of the tiles can vary substantially.
Recently there has been an increase in the interest of the presence of pyrite within slates. Pyrite (FeS2) is a mineral that can occur naturally in slates. Weathering of pyrite can result in the formation of iron oxide causing unsightly rust stains on the surfaces of tiles and runoff water or degradation due to expansive oxidation of pyrite.
Using X-ray diffraction and microscopic examination, where necessary, we at Ceram are able to determine the presence of pyrite within slates of interest and also able to evaluate the ability of slates to withstand accelerated durability tests.
Applications and Benefits
Confirm the absence or presence of pyrite within a slate to enable a decision to be made on the application of the material.
Form of Results
Quantitative analysis of the slate to determine the proportion of pyrite.
Quality and test methods of slate for roofing are detailed in
BS EN 12326-1: 2004
BS EN 12326-2: 2011 (supersedes BS 680-2).
Similar Tests for other Applications
Mineralogical characterisation by microscopy and X-ray diffraction enables full mineralogical characterisation of solid materials.