Eskişehir Lüle Stone

Eskişehir lüle taşı, bilimsel adı sepiolit olan, beyaz ya da nadiren kurşuni renkte, hafif ve gözenekli yapısıyla tanınan doğal bir mineraldir. Eskişehir ve çevresinde çıkarılan bu taş, yüksek su ve nikotin emme kapasitesi, ateşe dayanıklılığı ve işlenebilirliği ile öne çıkar. Fiziksel özellikleri arasında düşük sertlik (Mohs 2–2,5), kırılgan olmayan yapısı ve ısıya karşı yalnızca renk değiştirme özelliği yer alır. Genellikle pipo, biblo, takı, tespih ve süs eşyası üretiminde kullanılır.

Eskişehir lüle taşı is defined by several unique physical and technical characteristics:

• Chemical Formula: 2MgO·3SiO₂·2H₂O
• Porosity: Has a highly porous structure.
• Absorption Capacity: Can absorb nicotine and water.
• Heat Resistance: Resistant to heat; only changes color when exposed to high temperatures.
• Mechanical Strength: Does not break upon impact; exhibits structural flexibility.
• Water Dispersibility: Tends to disintegrate easily in water.
• Hardness: Has a hardness of 2 to 2.5 on the Mohs scale.

Due to these properties, it is used for various purposes in different industrial and craft fields.

Eskişehir lüle taşı is classified into seven distinct types based on size, weight, color, surface imperfections, pore structure, and vein patterns. This classification requires expert evaluation. The types and their applications are as follows:

1. Sıramalı: Primarily used in pipe production.
2. Birimbirlik: Used in the manufacture of pipe and biblo.
3. Pamuklu: Preferred for pipe manufacturing.
4. Daneli: Used in the production of small and women’s pipes and similar items.
5. Orta: Used in necklace, bracelet and cigarette mouthpiece production; also used in pipe chambers due to its nicotine-absorbing property.
6. Dökme: Used in the production of rosaries, decorative items and insulation materials; also finds application in certain industrial uses.
7. Cılız: Used in small decorative items, cigarette mouthpieces and necklaces; when ground into powder, it is also employed as a lining material.

After extraction from the mine, Eskişehir lüle taşı undergoes a series of procedures to transform it into a semi-finished state suitable for further crafting. The goal of these processes is to achieve the optimal softness and shapeability required for working. The stages are as follows:

1. Çırpma: Conducted to determine the economic value of the stone.
2. Saykal: The process of cleaning the stone of foreign materials.
3. Kabasının Alınması: Removal or fragmentation of sections identified during saykal as unsuitable for processing.
4. Ayrış (Yüzey Düzeltme): Smoothing of surface depressions using sharp-bladed knives.
5. Perdah: Fine surface leveling using thinner blades.
6. Tandırılama: Drying the stone in sunlight at an approximate 45° angle on racks.
7. Islak Aba ile Ovma: Rubbing dried stones with wet abrasive cloth to remove marks and polish the surface.
8. Ovma: After drying following wet abrasion, stones are smoothed using fine, soft fabric.
9. Yağlı Aba ile Ovma: Dried stones are polished using cloth impregnated with beeswax (oily abrasive).
10. Parlatma: After oily abrasion, the stone is finally polished with dry, soft cloths to complete the process.

After processing is complete, the stones are sorted according to type and category. They are wrapped in cotton or pelür paper and placed in special crates. During this stage, the stones are continuously inspected, and defective pieces are returned to the previous processing stage.

The production and related processes of Eskişehir lüle taşı are monitored in accordance with Article 20 of the Decree-Law No. 555 on the Protection of Geographical Indications. Inspections are carried out by the Eskişehir Chamber of Industry. Under the decisions of the relevant professional committee, inspections are conducted by the Chamber’s certified experts or, when necessary, by external specialists. Inspection covers all stages of production, including raw material, semi-finished and finished products.