Emery is a dark granular rock that consists of a mixture of corundum (aluminum oxide) and iron oxides (such as magnetite or hematite). It has been used as an abrasive and polishing compound for thousands of years, especially for metalworking, woodworking, and gem engraving. Emery takes its name from the Emeri Peninsula, on the Greek island of Naxos, where most of the emery used in the western world was produced since the classical Greek era.
The history of emery production in Naxos
Naxos is the largest of the Cyclades Islands, located in the Aegean Sea. It has a rich geological history, with various types of rocks and minerals, including marble, granite, quartz, and emery. Emery deposits are found in the northeastern mountainous side of the island, around the villages of Apeiranthos and Koronos. Emery has been known and exploited in Naxos since antiquity. The ancient Greeks called it “smyris”, after the port city of Smyrna (today Izmir in Turkey), which served as the main distribution hub for Naxos emery. The Romans called it “naxium”, naming it more succinctly for its place of origin. Dioscorides, Theophrastus, and Pliny all mention emery and its use as an abrasive in their writings.
In the early times, emery was recovered from loose boulders and blocks exposed by weathering. As the supply of easily accessed emery dwindled, other techniques were required. The exploitation of the mines was made in form of informal cooperatives of workers, who held shares and shared the costs of mining and the profits. The workers mined emery by constructing tunnels 50-250m deep. They used simple tools such as picks, hammers, chisels, and baskets to extract and transport the ore.
A considerable work was the creation of the skytrain, with which they transferred emery from the mines to Moutsouna, where they loaded it on ships. The skytrain was a cable railway system that consisted of 72 pillars, trolleys, loading facilities, engine rooms, storage areas, etc. It was constructed in 1926-1929 and started to operate in 1930. The network covered a distance of about 8 km and had a capacity of 150 tons per day. The skytrain operated until 1978 and is one of the very few preserved in Greece. It has been declared a preserved monument by the Ministry of Culture and is considered the most important monument of the modern industrial history of Greece.
For many years, emery was one of the most important Greek minerals and Naxos was the only emery producing area in Europe. The Naxos product was taken to Smyrna or other ports in sailing-vessels, whence it was reshipped to various destinations around the world. However, demand for emery decreased with the development of synthetic abrasives such as alumina and carbide in the 20th century. Today there are several Naxians who work about 1-2 months in the summer to collect a certain quantity each.
The uses and applications of emery
Emery has a hardness of about 8 on the Mohs scale, whereas pure corundum has a hardness of 9. Emery’s hardness has made it popular as an abrasive for various purposes. Some of the common uses of emery include:
- Woodworking – Emery paper is commonly used in woodworking for sanding and smoothing wood surfaces. It is also used for removing old finishes and preparing surfaces for painting or staining.
- Metalworking – Emery paper is used in metalworking for grinding and polishing metal surfaces. It is also used for removing rust or corrosion from steel, brass, copper, aluminum, and zinc, as well as cleaning them up prior to painting or welding.
- Gem cutting – Emery is used by lapidaries to engrave gems such as diamonds, rubies, sapphires, etc.
- Flooring – Emery is used as a slip-resistant material for floors and pavements. It is also used as a filler for asphalt and tarmac mixtures.
- Cleaning – Emery is used as a scouring agent for pots, pans, knives, etc.
- Other – Emery is used as a lubricant for metal parts, as a component of bung compounds for sealing barrels, as a raw material for metallic soaps, and as a chemical intermediate for various products.
A very fine emery dust is used by lens grinders, plate-glass manufacturers, and other industries that require high precision and quality. However, synthetic abrasives are often preferred for their more uniform grain sizes and properties.
Conclusion
Emery is a mineral that has a long and fascinating history of production and use. It is a natural resource that has contributed to the economic and cultural development of Naxos and Greece. It is also a versatile material that has many applications in different fields and industries. Emery is a testament to the ingenuity and creativity of human beings who have utilized the gifts of nature for their benefit.
References
- Emery and mines of Naxos – The Aegean Islands. Retrieved from https://www.aegeanislands.gr/pois/naxos-emery-and-mines-of-naxos-en/
- Daniel Russell – The Emery Mines of Naxos – mindat.org. Retrieved from https://www.mindat.org/article.php/153/The+Emery+Mines+of+Naxos
- Emery paper – Wikipedia. Retrieved from https://en.wikipedia.org/wiki/Emery_paper
- Emery | rock | Britannica. Retrieved from https://www.britannica.com/science/emery
- Emery (rock) – Wikipedia. Retrieved from https://en.wikipedia.org/wiki/Emery_%28rock%29
- OleoBasics – Emery Oleochemicals. Retrieved from https://www.emeryoleo.com/sites/default/files/2022-11/Emery-Oleochemicals-OleoBasics-Product-Portfolio-brochure.pdf
