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.
These early mountain forays set the stage for the permanent settlements that came later—after 11,000 years ago—when the climate had warmed, glaciers receded, and settlers had a chance to adapt to living at higher altitudes.