A part of the Rio Grande weaving tradition that goes back to Spanish Colonial times is called jerga. Historically, jerga was woven as a utilitarian fabric, used as a tarp, or carrier, or for wrapping things up. It was strictly a wool textile. Someone with wealth might demonstrate that by putting jerga down as a floor covering. It was woven in long strips and cut and seamed to make a piece of fabric of the desired size. And many of the jergas that survived to the present are very large.
The Spanish Colonial jerga was woven on four-harness looms using a straight twill, or, less commonly, as a diamond twill. Moving into more modern times, the jerga slowly evolved into a uniquely New Mexican variety of rag rugs.
Originally, jergas were probably pretty colorless, but many of the examples that survive have quite lively colors.
Moving into more modern times, the jerga slowly evolved into a uniquely New Mexican variety of rag rugs.