This document specifies a basic procedure for the identification of the petrographic type of natural aggregates. It applies for usual requirements for the procedure and terminology for simplified petrographic description. Precise petrographic identification, of technical mineralogy and petrography for civil engineering or specific end uses, requires further examination and is therefore excluded from the scope of this document.
NOTE 1 In principle, a qualified geologist (petrographer), with experience of materials used in civil engineering and aware of the composition of the deposit, has sufficient skills to sample and name the rock.
NOTE 2 For precise petrographic identification and technical requirements for specific applications, a non-exhaustive list of reference literature is given in the Bibliography.
This document applies only to natural aggregates. It is used to describe rocks and sediments. It does not apply to the description and identification of manufactured or recycled aggregates.
Informative Annex A provides guidance on the petrographic nomenclature by giving definitions of simple petrographic terms applicable to rock types used for aggregates.