blue

Concise Bible Dictionary:

This color was used extensively in the hangings of the tabernacle; in the vesture of the priests; and in the coverings of the vessels of the tabernacle when they were being removed. The color is typical of heaven: the whole of the tabernacle was “a shadow of heavenly things” (Ex. 26; Ex. 28).

Strong’s Dictionary of Hebrew Words:

Transliteration:
tkeleth
Phonic:
tek-ay’-leth
Meaning:
probably for 7827; the cerulean mussel, i.e. the color (violet) obtained therefrom or stuff dyed therewith
KJV Usage:
blue