3,955. The Different Materials of the Bigdei Kehuna

Hilchos Klei HaMikdash 8:13

Wherever the Torah says sheish or bad, it refers to linen; techeiles refers to sky-blue wool. This shade is lighter than plain “blue.” Argaman refers to red [purple] wool and tolaas shani refers to (scarlet) wool that was dyed with pigment from a particular worm.

Hilchos Klei HaMikdash 8:14

When the Torah says sheish or sheish mashzar, one must use six-ply threads; when it says bad, a garment is valid if even a one-strand thread is used. Nevertheless, it is optimum for six-ply threads to be used. When the Torah says mashzar alone (i.e., with sheish), an eight-ply thread must be used.