Ancient Purple Dye Factory Was a Multi-Use Seasonal Complex

A study published in the journal PLOS ONE reveals that the ancient purple dye production site at Tel Shikmona, near Haifa, operated as a versatile, multi-purpose complex whose function changed seasonally. During the 8th century BCE, inhabitants utilized the structures for olive pressing in the fall, animal husbandry and dwelling in the winter, and textile production in the spring, all while maintaining the primary industry of producing the valuable purple dye.

The industrial complex at Tel Shikmona is considered the largest purple dye production facility in the Eastern Mediterranean from the Iron Age. Excavations conducted in 2023 by a team from the University of Haifa uncovered evidence that during the reign of King Jeroboam II, the site served multiple industries concurrently. Researchers found that the spaces were adapted for different uses throughout the year.

This seasonal adaptation was facilitated by a planned method of spreading ash layers over animal dung. This practice served to disinfect the areas, eliminate odors, and control pests before the spaces were repurposed for industrial activities. The findings are based on advanced microscopic analysis of soil samples, which identified wood ash, olive pits, and animal droppings invisible to the naked eye.

Dr. Isaac Ogloblin-Ramirez explained that while excavations typically reveal large structures and artifacts, the soil layers can preserve a much more detailed story, allowing reconstruction of not only what was done but how the usage changed over time. This seasonal operational model challenges previous archaeological assumptions, as Dr. Golan Shiloah noted that the common tendency is to identify a structure solely by its most prominent use, like olive oil production, without considering its function during other parts of the year.

The findings, which also involved Sonia Pinski and Prof. Ayelet Gilboa, indicate sophisticated economic planning and operational flexibility aimed at maximizing the use of labor and resources. Prof. David Frizman concluded that the integration of archaeological and micro-archaeological findings opens new avenues for understanding ancient activities, highlighting that efficiency and maximum resource utilization were as important in ancient societies as they are today.