BGS Rock Classification Scheme

Ironstone, siliceous

Code FSTSI
Description Ironstone, siliceous
Qualifiers siliceous      
Definition Sedimentary rock (>15wt% iron), no recognisable depositional texture with particles >50% iron-bearing minerals (15wt% iron). 5-20% silica of biogenic or chemical origin. Particle size not defined.
Linked data http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/FSTSI

CAVEAT

"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.