To discover the makeup of textiles in order to place them historically.
Textile analysis can aid everyone from forensic anthropologists searching for clues to museum conservators hoping to identify and preserve an antique dress.
Experts first need to place an item historically by understanding the fibers and dyes involved. Then conservators rely on analytical tools to assess the makeup and age of a piece of cloth, then consider the safest methods for conservation.
How to use textile analysis to identify and date a piece of fabric.
Doing it Naturally
To establish the age, strength and weave of an item, a fiber sample is removed.
The material is examined under a polarizing light microscope to see the structure and color of the fiber. If natural fibers (wool, cotton or linen) are present then the textile can be more than 80 years old. Whereas man-made fibers were not in heavy use until the 1920s.
A textile analyst must also understand and examine weaving techniques which helps determine the type of material and its relative strength.
A Warped View
It's not enough to just know the makeup of a textile, as natural fibers are still in use today. Often, the best tool for analysis is simply the experienced eye of a conservator. A close inspection of stitching and design can do more to identify a textile than anything else. A knowledgeable conservator can attribute weaving techniques to different countries and eras.
To Dye For...
Dye testing is also used to understand the provenance of a textile. When natural dyes are suspected, samples of the fiber are subjected to analysis to find out the dyes used and then compared to a standard database of dyes.
Other methods, such as Thin Layer Chromatography and High Pressure Liquid Chromatography are also used. Chromatography is a chemical analysis that separates components into various parts.
In rare and important cases, a destructive method of analysis, such as radiocarbon dating is used to establish age.