First of all they bridged over the zones of sea which surrounded the ancient metropolis, making a road to and from the royal palace. And at the very beginning they built the palace in the habitation of the god and of their ancestors, which they continued to ornament in successivegenerations, every king surpassing the one who went before him to the utmost of his power, until they made the building a marvel to behold for size and for beauty. And beginning from the sea they bored a canal of three hundred feet in width and one hundred feet in depth and fifty stadia in length, which they carried through to the outermost zone, making a passage from the sea up to this, which became a harbour, and leaving an opening sufficient to enable the largest vessels to find ingress. Moreover, they divided at the bridges the zones of land which parted the zones of sea, leaving room for a single trireme to pass out of one zone into another, and they covered over the channels so as to leave a way underneath for the ships; for the banks were raised considerably above the water. Now the largest of the zones into which a passage was cut from the sea was three stadia in breadth, and the zone of land which came next of equal breadth; but the next two zones, the one of water, the other of land, were two stadia, and the one which surrounded the central island was a stadium only in width. The island in which the palace was situated had a diameter of five stadia. All this including the zones and the bridge, which was the sixth part of a stadium in width, they surrounded by a stone wall on every side, placing towers and gates on the bridges where the sea passed in. The stone which was used in the work they quarried from underneath the centre island, and from underneath the zones, on the outer as well as the inner side. One kind was white, another black, and a third red, and as they quarried, they at the same time hollowed out double docks, having roofs formed out of the native rock. Some of their buildings were simple, but in others they put together different stones, varying the colour to please the eye, and to be a natural source of delight. The entire circuit of the wall, which went round the outermost zone, they covered with a coating of brass, and the circuit of the next wall they coated with tin, and the third, which encompassed the citadel, flashed with the red light of orichalcum.
In numismatics, orichalcum is the name given to a brass-like alloy of copper and zinc used for the Roman sestertius and dupondius. Very similar in composition to modern brass, it had a golden-yellow color when freshly struck. In coinage, orichalcum's value was nearly double reddish copper or bronze. Because production cost was similar to copper or bronze, orichalcum's formulation and production were highly profitable government secrets.
In Natural History (xxxiii 95) Strabo (64 BC - 23? A.D.) wrote about orichalcum, “There is a stone in the neighborhood of Andeira which when burned becomes iron, and then when heated in a furnace with a certain earth distills pseudargyros and this with the addition of copper makes the mixture called by some oreichalkos.” Pseudargyros (Pseudo-silver) is presumably a term for zinc, while oreichalkos is orichalcum, brass.
The name “orichalcum” also refers to a fictional or legendary metal that is found in several ancient works of literature. Included among these is the story of Atlantis, written by Plato. This metal was said to have originated from mines in Atlantis and was the most valuable metal known by man, apart from gold. The use of the term “orichalcum” in this context should not be confused with the actual alloy used for Roman coinage.