The Hebrew word translated as “chariot” in this passage actually refers to a palanquin-a portable couch or chair in which kings were carried from place to place by royal servants. Poles were fastened to each side of the palanquin.
Four servants would then hoist the king in his chair and place the poles on the shoulders. Solomon’s gold and silver palanquin had a purple awning or cover to protect him from the sun. Purple was the color that signified royalty.
SONG OF SOLONS 1:9-10 – King Solomon made himself a chariot [carriage, NIV] of the wood of Lebanon. He made the pillars [posts, NIV] thereof of silver, the bottom [base, NIV] thereof of gold, the covering of it of purple.