Trona

How does it form?

Trona is a non-marine evaporite mineral deposited as closed, salty lakes dry up. Several special conditions have to come together: volcanic ash and hot springs bring plenty of sodium into the lake; the lake basin is a hollow that does not drain; the climate is at times arid or semi-arid; and the water must have a pH of 10–12, be shallow and be 25–40 °C (İMİB).

Because trona dissolves easily in water, it never crops out at the surface; its deposits lie underground in young Tertiary basins. No trona deposit older than the Tertiary is known: the deposits of the Green River Formation in Wyoming and of China’s Wucheng basin are Eocene, and the Beypazarı deposit is Middle–Upper Miocene.

What is it used for?

• Soda ash: Trona is crushed and heated or dissolved in water to make soda ash (sodium carbonate). In the United States about 45 percent of soda ash goes into glass, 28 percent into chemicals and 5 percent into soap and detergents (USGS). In glassmaking it lowers the melting point of quartz sand.
• Baking soda: Sodium bicarbonate (baking soda) is also obtained from trona solutions.
• Other uses: Removing sulfur from flue gas and an animal-feed additive (according to MTA these are small shares in Türkiye), as well as pulp and paper and water treatment.

In Türkiye

Türkiye’s trona deposits are in Ankara, in the districts of Beypazarı and Kazan (Kahramankazan). The deposits are underground; at both sites trona is mined by solution mining, in which water and a solvent are injected through wells and the dissolved trona is pumped out.

The Beypazarı deposit lies in a Miocene lake basin about 20 km north-west of the district centre, in trona beds 0.2–11 m thick interlayered with clay, gypsum and clay shale. MTA found it by chance in 1979 while drilling for coal north of Beypazarı; it was handed over to Etibank in 1985. According to the İMİB report the deposit holds about 235 million tons of reserves containing 56 percent or more trona. The Kazan deposit was found by a foreign company in 1998–2000 (the report gives two different years) and is the first deposit in the world found by exploration aimed at trona. 117 boreholes proved more than 600 million tons at a grade of about 31 percent; the 15 trona beds lie at roughly 420–850 m depth and the thickest reaches 109 m. According to İMİB, Türkiye’s total trona reserve is about 884 million tons.

Production comes from these two deposits. The Eti Soda plant in Beypazarı was founded in 1998 and began production in 2009; according to Wikipedia its partners are Ciner Holding (74 percent) and Eti Maden (26 percent), and its yearly capacity is about 1 million tons of soda ash and 100,000 tons of baking soda. According to the 2026 USGS summary, Türkiye produced about 6 million tons of natural soda ash in 2025: after the United States (12 million tons) it is the second-largest natural soda producer. Counting all soda ash, synthetic included, it is third after China and the United States. The USGS puts Türkiye’s soda ash reserves at 840 million tons, second only to the United States. In 2021–24, 89 percent of US soda ash imports came from Türkiye.