Isolated examples of copper-zinc alloys are known in China from as early as the fifth millennium BCE; in small numbers from a number of third millennium BCE sites in the Aegean, Iraq, the United Arab Emirates, Kalmikia, Turkmenistan and Georgia; and from second millennium BCE sites in West India, Uzbekistan, Iran, Syria, Iraq and Palestine.

The compositions of these early "brass" objects are very variable and most have zinc contents of between five percent and fifteen percent by weight, which is lower than in brass produced by cementation.

These may be "natural alloys" manufactured by smelting zinc rich copper ores in reducing conditions.

Many have similar tin contents to contemporary bronze artifacts and it is possible that some copper-zinc alloys were accidental and perhaps not even distinguished from copper.

However, the large number of copper-zinc alloys now known suggests that at least some were deliberately manufactured and many have zinc contents of more than twelve percent, which would have resulted in a distinctive golden color.

Assyrian cuneiform tablets from the eighth–seventh century BCE mention the exploitation of the "copper of the mountains,” which may refer to "natural" brass.

Oreichalkos, the Ancient Greek translation of this term, is later adapted to the Latin aurichalcum, meaning "golden copper" which becomes the standard term for brass.

Plato, describing Atlantis in the Critias and the Timaeus in the fourth century BCE, knew oreichalkos as rare and nearly as valuable as gold.

Pliny describes how aurichalcum had come from Cypriot ore deposits, which will be exhausted by the first century CE.