Onyx Stone

Onyx stone is a type of travertine, mineralogically derived from calcite (CaCO₃), characterized by a banded appearance and ornamental qualities. Although geologically classified within travertine formations, it differs due to its distinct colored bands and potential for decorative use. Its colorful appearance results from the precipitation of calcium carbonate carried by cold bicarbonate-rich groundwater as it emerges to the surface, in environments containing various metal ions such as iron and manganese. During this process, accumulated different minerals form successive bands in shades of greenish, yellowish, brownish, and grayish hues. Band thicknesses can vary from a few centimeters up to 75 cm.

Onyx typically forms in veins or lens-shaped structures, with thicknesses ranging from a few centimeters to 75 cm. Structurally, it exhibits low porosity, excellent polishability, and high aesthetic value. These properties make onyx stone suitable for the production of decorative items and jewelry. In popular usage, this stone is sometimes referred to as “veined agate” or “water marble.”

A total reserve of approximately 1,307,000 m³ of onyx stone has been identified across Türkiye. The majority of these reserves (76.51%) are located within the boundaries of Manisa Province, particularly around the village of Saraycık in the Demirci district. The second largest reserve group is found in Bolu Province (22.95%). Other reserves are distributed in smaller proportions across various other provinces. Onyx production in Türkiye increased during the 1980s, but domestic output has since declined due to the influx of cheaper products from China and Pakistan.

Kırşehir Province is another significant center where onyx stones occur in banded travertine form. The main formation areas in this province include Terme (central Kırşehir), Avcı (Mucur, Kırşehir), and Bekdik (Aksaray). In these regions, banded travertine formations appear as veins or lenses within travertine layers extending up to 10–50 meters in width and 1.5 kilometers in length.

The “Kırşehir Onyx” gained regional recognition as a product name during the 1980s and developed a recognized brand status within Türkiye. At that time, dozens of workshops operated in Kırşehir. Processed onyx products were utilized in the giftware and jewelry sectors. Today, only two small-scale workshops continue operations, sourcing their raw material from neighboring provinces.

The Terme and Bekdik areas are no longer used for stone production, as they are currently utilized for geothermal energy generation, physical therapy, thermal tourism, and greenhouse farming. The Avcı (Mucur) area retains production potential but remains inactive at present.

Onyx stones extracted from the Avcı area are suitable for decorative use due to their distinct physical and mechanical properties. The density of these stones is 2.63 g/cm³, indicating a compact and durable structure. Samples exhibit banded veins in white, yellow, and amber-yellow tones. With low porosity, these stones respond exceptionally well to polishing and surface treatments. Their ease of workability also makes them among the preferred natural stones for jewelry and decorative item production.

Nevşehir Province is an important center for intangible cultural heritage and traditional crafts. Onyx stone craftsmanship is practiced in the regions of Ürgüp, Avanos, Uçhisar, and Göreme. Additionally, in the district of Hacıbektaş, 69-year-old stone artisan Besim Badem processes approximately 30 tons of onyx stone annually, producing thousands of decorative items and jewelry. These products are sold in local souvenir shops.

^{Processed Onyx Stones (}Anadolu Agency⁾

Onyx stone craftsmanship in Kırşehir was first initiated in 1949 within the framework of the Kırşehir Male Art Institute. Today, stone processing activities consist of the following stages:

Products made from onyx stone possess both visual and functional qualities due to their natural aesthetics, colorful banded structure, and polishable surface. These products can generally be categorized into two main groups: giftware and jewelry.

In the giftware category, prominent items include animal and fruit figures, liqueur and coffee sets, incense burners, candy dishes, trays, bowls, nameplates, and keychains. These items attract interest for both their decorative and functional attributes. Symbolic animals such as elephants, eagles, and owls are commonly chosen for figurative pieces, while fruit forms like apples, pears, and grapes are frequently used.

^{Giftware Items Made from Onyx Stone (}Anadolu Agency⁾

In the jewelry category, products include necklaces, bracelets, bangles, earrings, rings, brooches, and prayer beads. The polished surface and semi-translucent texture of onyx add aesthetic value to these pieces, making them popular among natural stone jewelry enthusiasts. These items are sold primarily in tourist areas, local craft markets, and souvenir shops, and are regarded as representative examples of the region’s cultural craftsmanship.