Analysis of the elements that make up the fabric of a rock to determine the response of that rock to stress. In a rock the three-dimensional pattern comprising the distribution, shape, size, and size distribution of crystals or grains constitutes the fabric, e.g. bedding in sedimentary rocks, or metamorphic banding (see gneiss). Fabric analysis is important in engineering because, for example, rock strength parallel to banding can differ markedly from that perpendicular to banding. In soils, fabric is analysed by comparing the strength of an undisturbed sample with its strength when remoulded; this describes the sensitivity of the soil.