Your description should be in the form of a succinct paragraph with this approximate order of features. Standard abbreviations are acceptable. With some outcrops, variation between units may be minor; if so, initial description should be thorough, with subsequent entries condensed to suit rock character.

A. Color, fresh and weathered (of wet or dry rock?) - include rock name (e.g. quartz arenite) early in first descriptive phrase

B. Induration, fresh and weathered

C. Dominant grain size - gravel (calcirudite), sand (calcarenite), silt, clay (calcilutite or micrite) or any combination of sediments as in a sandy conglomerate

D. Sorting or equigranularity - well, moderately, poorly

*E. Textural maturity (immature, submature, mature, supermature)

F. Grain types/Mineralogy - describe clasts (allochems) including fossil types, and estimate the their approximate percentages

*G. Grain shapes (e.g. Angularity/Rounding - round, sub-round, sub-angular, angular, very angular; character of fossil abrasion may be more appropriate for carbonate rocks)

H. Orientations or fabric of shaped grains (e.g. micas or fossils)

I. Nature and amount of cement or matrix, if any

Note: If dealing with a conglomerate, both the clasts and the matrix must be described using this format, as well as the rock as a whole

*J. Cementing agent - silica, calcite, iron oxides, clays

K. Nature & amount of pores (porosity), and any indications of permeability (is this fresh rock?)

L. Types and degree of diagenetic alteration, if any

M. Sedimentary features (if any) - e.g. soft sediment deformation, bioturbation, staining by oxides or organic matter, ripple-lamination, mud cracks, etc.

N. Bedding (if present) - nature of bedding contacts (e.g. sharp vs. gradational), thickness; cross-beds, laminations, etc.,

O. Fossils - delineate any fauna/flora present to as low a taxonomic level as possible

P. Possible depositional environments (NOTE: some geologists advocate NEVER including interpretations in field notes; others feel that it helps to make interpretations based on initial impressions out in the field)

* must be altered, or deleted, when describing some organic or chemical rocks

The following is an example: This light gray, volcanic litharenite is moderately-well indurated but upon weathering becomes medium to dark gray, and friable. It is fine- to medium-grained and moderately well-sorted. This rock contains angular to sub-round grains of sand-sized quartz and lithic fragments of pumice and plagioclase feldspar. It has a submature texture cemented with opaline silica. Calcite originally present (e.g. fossils) has been replaced by silica during subsequent diagenesis and/or metamorphism. Sedimentary structures present are small-scale cross-laminations. No bedding is seen in this hand specimen. Fossils present in this rock include a few thin-shelled gastropods and pelecypods. This sandstone was probably deposited in a shallow, near shore marine setting in close proximity to a volcanic terrane.