made of gold: describing an object formed from or overlaid with the metal gold
This is a plain describing word: it tells you that a thing is made of gold. It attaches to objects, never to people, and across the New Testament those objects are almost always parts of worship and royalty: lampstands, bowls, censers, an altar, sashes, crowns, a cup, a measuring rod, and the gold-covered furnishings of the old tabernacle.
The word itself carries no hidden meaning; its interest lies in what gold signals wherever it appears. Gold marks the highest worth and a kind of permanence, so it fits the furniture of God's presence: the golden lampstands among which Christ walks, the golden bowls of incense that are the prayers of God's people, the golden altar and crowns of heaven's throne room. Nearly all of these uses cluster in Revelation, which pictures heaven as a place of gold.
But gold marks value, not holiness. The same word describes idols of gold that people refuse to stop worshiping, and the golden cup in the hand of Babylon the prostitute, gleaming on the outside yet full of filth within. The metal is precious in every case; whether the object is holy depends entirely on what it is and who holds it.