Nevşehir Pumice is a natural volcanic mineral specific to the province of Nevşehir, located in the Central Anatolia Region of Türkiye. Formed as a result of volcanic eruptions, it features a porous and glassy structure. With its lightness, high porosity, and chemical inertness, it holds a significant place among industrial raw materials.

Türkiye possesses approximately 15.8% of the world’s pumice reserves, and Nevşehir alone accounts for 17% of the national reserves, making it a strategic center in this field. About 20% of all pumice mining licenses in Türkiye are located in Nevşehir.

Nevşehir Pumice was registered as a designation of origin on December 8, 2022, by the Turkish Patent and Trademark Office. This registration guarantees the authenticity and quality of pumice produced within the province of Nevşehir using specified production methods and characteristics.

^{Pumice Mine (Anadolu Agency)}

Formation

Pumice is an extrusive volcanic rock formed when magma rapidly cools and the gases within it quickly escape during volcanic activity. This rapid cooling process results in pumice’s unique sponge-like, porous structure. Its low density allows it to float on water. Its thermal and acoustic insulation properties, resistance to high temperatures, and chemically inert structure make it an attractive raw material for various industries.

Nevşehir Pumice extracted from quarries is not directly ready for use. It must be processed through drying and sieving at dedicated facilities. After processing, the pumice is carefully classified according to grain sizes, which allows for its distribution across different sectors based on specific requirements:

• 8–16 mm grain size: Mainly used in the construction industry for pumice blocks, lightweight concrete, and plaster applications. It is also favored in agriculture as a soil conditioner.
• 4–8 mm grain size: Commonly used in the textile industry, particularly in the bleaching and abrasion of denim fabrics.
• 0–4 mm (fine aggregate) grain size: Utilized in the chemical industry as a filler, filter material, polishing, and abrasive agent.

Physical and Chemical Properties

Nevşehir Pumice is highly suitable for industrial use due to its physical and chemical properties. Its color ranges from white to cream, with a homogeneous distribution of pores and a glassy texture. These features result from the rapid cooling and gas release during volcanic eruptions. With a medium hardness rating of 5.5 to 6.0 on the Mohs scale, pumice has a low density; its specific gravity ranges between 2.33 and 2.35 g/cm³, and its dry bulk density ranges from 502 to 830 kg/m³ depending on grain size. This low density allows it to float on water. It also has a high water absorption capacity, ranging from 22.75% to 40.30%, which increases with pore structure and grain size. Its thermal conductivity lies between 0.112 and 0.184 W/mK, offering excellent insulation properties.

Chemically, Nevşehir Pumice contains high levels of silicon dioxide (SiO₂), ranging from 65.79% to 72.00%, which gives it an acidic character. It also contains 12.74–17.11% aluminum oxide (Al₂O₃), 3.20–4.55% potassium oxide (K₂O), and 1.20–4.70% iron oxide (Fe₂O₃). Being chemically inert, it is safely used in various chemical applications. Thanks to this composition and its physical features, Nevşehir Pumice finds widespread and efficient use in construction, agriculture, textiles, and chemical industries.

^{Pumice Mine (Anadolu Agency)}

Applications and Uses

Construction Sector

Nevşehir Pumice is used in the production of modern building materials. It serves as the main aggregate in pumice blocks (bims), which provide superior thermal and acoustic insulation, enhancing energy efficiency. Their lightweight reduces seismic load, contributing to safer buildings. It is also used in lightweight plaster and mortar production for improved insulation and ease of application. In lightweight concrete production, it reduces structural weight while enhancing thermal and acoustic properties. Its high fire resistance offers additional safety benefits.

Textile Sector

Widely used in the denim industry to achieve the "stone-washed" or "distressed" appearance of jeans and other denim products. Pumice stones are tumbled with denim in industrial washing machines to abrade and bleach the fabric surface, resulting in a softened texture and desirable aesthetic.

Agricultural Sector

In agriculture, pumice serves as a soil conditioner. Its high porosity enhances soil aeration, supporting better oxygen uptake by roots. It improves water and nutrient retention, regulating soil moisture and increasing fertilizer efficiency. Pumice is also used in soilless agriculture (hydroponics and cocopeat mixes), providing optimal root support and nutrient access.

Chemical and Other Sectors

Pumice is used as a filler in many chemical products. It functions as a volumizing and lightweight component in surface coatings, paints, rubber, and plastics. In industrial filtration systems, it acts as a filtering medium to trap particles in water and wastewater treatment. It is also used in polishing and abrasive powders for surface finishing.

Production Process and Quality Control

The production of Nevşehir Pumice begins with the extraction from quarries. The raw material is transported to crushing and screening facilities. Initially, coarse sieving is performed, followed by separation based on grain size, typically into three main sizes: 8–16 mm, 4–8 mm, and 0–4 mm. After classification, the products are packaged or stored in silos, ready for shipment.

The designation of origin for Nevşehir Pumice ensures a strict control mechanism to protect the quality and uniqueness of the product. Inspections are coordinated by the Association of Pumice Industry (BİMS), with the participation of experts from the Nevşehir Provincial Directorate of Industry and Technology and Nevşehir Hacı Bektaş Veli University Pumice Application and Research Center. These inspections occur periodically (at least once a year) or upon complaint.

The primary goal of these inspections is to verify that production occurs within Nevşehir province, by the specified distinguishing characteristics and production methods. The correct and proper use of the "Nevşehir Pumice" label and the designation of origin logo on the product or its packaging is also monitored.