More fully in Hesychius s.v. ("a territory, in which there are precious stones and gold, in India"), and similar material elsewhere -- wealth being the constant point of comment.
Despite the initial S-, this is the Ophir mentioned twice, for its mineral wealth, in the Septuagint (Job 22.24, 28.16) and famous also in the opening stanza of John Masefield's poem Cargoes: "Quinquireme of Nineveh from distant Ophir, | Rowing home to haven in sunny Palestine, | With a cargo of ivory, | And apes and peacocks, | Sandalwood, cedarwood, and sweet white wine". The personal name Ophir appears also in Genesis 10.29 (one of the sons of Joktan, of the line of Shem); and for Ophir as a toponym see also e.g. Psalms 45.9, Isaiah 13.12.
Modern attempts to locate Ophir have veered wildly between (e.g.) Afghanistan, Australia, Brazil, the Indus Valley, Peru, the Philippines, the Solomon Islands, Sri Lanka, and Zimbabwe.