This 1400-year period takes us from the first appearance of bronze - an alloy of copper and tin - to the beginning of iron use. The first of these developments seems to have had a profound effect on the prosperity of the inhabitants of Argyll and Bute - and in particular the area around Kilmartin Glen - as they were able to control the flow of the new metal (bronze) and/or of the Irish copper that formed its main constituent, as it travelled north-eastwards from Ireland to a flourishing centre of bronze production in north-east Scotland, via the Great Glen. The first few centuries of the Early Bronze Age (covered in the first part of this section) was thus a kind of 'golden age' in this part of Scotland, with new-found prosperity being shown off in ostentatious funerary monuments and personal possessions. There is also evidence for Early Bronze Age settlements, principally at Kilellan and Ardnave on Islay. The archaeological record for the succeeding centuries between 1900 BC and c 1100 /1000 BC is thinner, with no sign of a continuation of the conspicuous consumption that marked the preceding centuries, although some trends in funerary and monumental practices, and some changes in material culture can be discerned. While there is a marked hiatus in activity in Kilmartin Glen from around 1000 BC - the possible reason for which is discussed below - elsewhere there is evidence that the inhabitants of Argyll and Bute were playing an active role in the extensive Atlantic Late Bronze Age network, in which bronze artefacts, and acts of competitive conspicuous consumption that involved them, featured prominently.