Amber
The substance traditionally rendered "amber" appears three times, all in Ezekiel, where it describes the visual quality of the divine appearance. UPDV translates the term as "glowing metal."
In the Opening Vision
The first occurrence belongs to the inaugural theophany at the river Chebar: "And I looked and saw that a stormy wind came out of the north, a great cloud, with a fire infolding itself, and a brightness round about it, and out of the midst of it as it were glowing metal, out of the midst of the fire" (Eze 1:4). Later in the same chapter, the figure on the throne is described in the same terms: "And I saw as it were glowing metal, as the appearance of fire inside it round about, from the appearance of his loins and upward; and from the appearance of his loins and downward I saw as it were the appearance of fire, and there was brightness round about him" (Eze 1:27).
In the Temple Vision
When the same figure appears to Ezekiel in the second great vision, the comparison returns: "Then I looked and saw a likeness as the appearance of fire; from the appearance of his loins and downward, fire; and from his loins and upward, as the appearance of brightness, as it were glowing metal" (Eze 8:2).
The image is consistent across the three passages — a brightness like molten or glowing metal at the heart of the fire, used to render what Ezekiel saw of the figure on the throne.