Exodus 25:4 New English Translation

⁴blue,^[a] purple,^[b] scarlet,^[c] fine linen,^[d] goats’ hair,^[e]

Exodus 25:4 sn The blue refers to dye made from shellfish. It has a dark blue or purple-blue, almost violet color. No significance for the color is attached.
Exodus 25:4 sn Likewise this color dye was imported from Phoenicia, where it was harvested from the shellfish or snail. It is a deep purple-red color.
Exodus 25:4 sn This color is made from the eggs and bodies of the worm coccus ilicus, which is found with the holly plant—so Heb “worm of brilliance.” The powder made from the dried maggots produces a bright red-yellow color (W. C. Kaiser, Jr., “Exodus,” EBC 2:452). B. Jacob takes the view that these are not simply colors that are being introduced here, but fabrics dyed with these colors (Exodus, 765). At any rate, the sequence would then be metals, fabrics, and leathers (v. 5).
Exodus 25:4 sn This is generally viewed as a fine Egyptian linen that had many more delicate strands than ordinary linen.
Exodus 25:4 sn Goat’s hair was spun into yarn (35:26) and used to make the material for the first tent over the dwelling. It is ideal for tenting, since it is loosely woven and allows breezes to pass through, but with rain the fibers expand and prevent water from seeping through.

New English Translation (NET)