While many islands of the Greek archipelago are rich in marble or fertile soil, Milos, an island in Greece, held a treasure that shaped the early development of human civilization in the region: obsidian.
This volcanic glass, prized for its sharpness and durability, became one of the most sought-after materials of the prehistoric world. Archaeological discoveries of Melian obsidian dating back to the Upper Palaeolithic provide some of the clearest evidence for early seafaring in Greece.
The circulation of obsidian from Milos demonstrates that Aegean peoples were capable of organized navigation as early as 11,000 years ago, long before the rise of the Minoans or Mycenaeans.
Molten lava cools rapidly to form obsidian, a natural glass with a razor-sharp edge. In antiquity, it was prized for blades, scrapers, and projectile points, offering cutting power superior to most other stones. The volcanic landscape of Milos made the island the primary source of this material in the Aegean. From Milos, obsidian spread across the Greek mainland, the Ionian Islands, and the coasts of Asia Minor. Archaeologists have traced this distribution through chemical analysis, linking artifacts found at distant sites directly back to the Melian quarries.
Obsidian tools were essential for survival in early societies. They were used to cut grain, prepare hides, and shape wood, and they also appeared in ritual contexts, sometimes placed as grave offerings. The widespread circulation of obsidian from Milos, Greece, highlights not only its practical value but also the existence of a sophisticated network of exchange long before written history.
The earliest evidence of obsidian outside of its island of origin comes from the cave of Franchthi in the Argolid. There, archaeologist Thomas W. Jacobsen of Indiana University uncovered obsidian blades dating to the 11th millennium BC. This discovery is of extraordinary importance, showing that even during the Upper Palaeolithic period -- long before the rise of farming communities -- Aegean peoples were capable of navigating the open sea.
Franchthi Cave lies on the mainland of Greece, nearly 120 kilometers (75 miles) from Milos. To obtain obsidian, the inhabitants would have had to cross significant stretches of water. This journey implies more than accidental drift; it points to deliberate planning, the use of seaworthy vessels, and knowledge of currents and wind patterns. In other words, it demonstrates the existence of a maritime tradition stretching back at least 11,000 years.
The use of obsidian did not cease with the end of the Palaeolithic. On the contrary, its significance increased during the Mesolithic and Neolithic periods. As communities adopted agriculture and settled into permanent villages, there was a greater demand for sharp tools. Obsidian blades were used for harvesting cereals, processing hides, and woodworking. In this era, obsidian became one of the most commonly traded materials in the Aegean.
By the 6th millennium BC, Melian obsidian was found across a wide geographical area. It reached Crete, the Ionian Islands, and the coasts of Asia Minor. This distribution suggests an intensification of maritime activity. Boats capable of carrying people and goods became a vital part of life in the Aegean. The circulation of obsidian thus provides a material record of the first organized sea routes in Greece.
The archaeologist Colin Renfrew believed that obsidian trade was not random but part of a structured system of exchange. Settlements in the Cyclades, such as those of the Early Cycladic I period (3200-2800 BC), show clear signs of stone-working specialization. Craftsmen used obsidian to produce bowls, palettes, and fine blades. Elaborate vessels appear later in the Early Cycladic II period (2800-2300 BC). The presence of obsidian workshops at several sites demonstrates that this volcanic glass had become central to Cycladic craftsmanship and culture.
These developments also show that the Aegean peoples possessed a clear sense of navigation and trade. Obsidian was transported not only for utility but also for prestige. Its circulation reflects the growing social complexity of early Greek societies. It served as a medium that connected islands, coasts, and communities into a wider maritime network.
We cannot overstate the significance of obsidian from Milos, Greece, for the history of Greek seafaring. The archaeological record shows that organized navigation existed thousands of years earlier than once believed. The transportation of obsidian across open waters indicates advanced planning, knowledge of geography, and skill in boat construction.
This pushes the history of Aegean seafaring back to at least the 11th millennium BC. For comparison, the famous Minoan thalassocracy does not emerge until the second millennium BC. The evidence from Milos demonstrates that people had laid the foundations for this maritime power long before. The sea was not a barrier for early Aegean peoples but a pathway that connected them and shaped their identity.
Obsidian was not only practical but also symbolic. Archaeologist Christos Doumas found that people often placed obsidian objects in burials, suggesting that the stone held ritual significance -- perhaps as a symbol of strength, purity, or protection. Its sharp, glass-like quality may have been associated with divine or supernatural power. In this way, obsidian connected the daily life of the Aegean peoples with their spiritual world.
The circulation of obsidian also hints at early ideas of value and exchange. Long before the invention of coinage, obsidian functioned as a medium of wealth. It was portable, durable, and highly prized. Its presence across the Aegean shows that people recognized its special worth, both economically and symbolically.
The history of obsidian from Milos reveals an extraordinary legacy. For over 11,000 years, the ancient Greek engaged in maritime activity, crossing the sea to obtain resources, exchange goods, and establish cultural connections. This tradition predates the monumental achievements of the Bronze Age by thousands of years and shows that seafaring was not a late innovation but an integral part of Greek identity from the very beginning.
The story of Melian obsidian underscores the deep roots of Aegean civilization. It reminds us that the achievements of the Minoans and Mycenaeans rested on a foundation laid in prehistory. Long before palaces rose on Crete or citadels on the mainland, obsidian cutters, sailors, and traders shaped the destiny of the Greek world. Their journeys across the Aegean made possible the later flourishing of Greek culture.