A gold lunula was a distinctive type of late Neolithic, Chalcolithic, and—most often—early Bronze Age necklace, collar, or pectoral shaped like a crescent moon. Most are from Prehistoric Ireland. They are normally flat and thin, with roundish spatulate terminals that are often twisted to 45 to 90 degrees from the plane of the body. Gold lunulae fall into three distinct groups, termed Classical, Unaccomplished and Provincial by archaeologists. Most have been found in Ireland, but there are moderate numbers in other parts of Europe as well, from Great Britain to areas of the continent fairly near the Atlantic coasts. Although no lunula has been directly dated, from associations with other artefacts it is thought they were being made sometime in the period between 2400 and 2000 BC; a wooden box associated with one Irish find has recently given a radiocarbon dating range of 2460–2040 BC.

The prehistory of Ireland has been pieced together from archaeological evidence, which has grown at an increasing rate over the last decades. It begins with the first evidence of permanent human residence in Ireland around 10,500 BC and finishes with the start of the historical record around 400 AD. Both the beginning and end dates of the period are later than for much of Europe and all of the Near East. The prehistoric period covers the Palaeolithic, Mesolithic, Neolithic, Bronze Age and Iron Age societies of Ireland. For much of Europe, the historical record begins when the Romans invaded; as Ireland was not invaded by the Romans its historical record starts later, with the coming of Christianity.