Our company founder Mr.Xingming Leiwho is the famous geographical expert in Chinahas been committed to the development and utilization of Ziyang blue-black natural slate for more than 20 years. This natural slate has passed the tests of Chinese national stone quality supervision and English EN testing and now is mainly applied in roofing construction. According to the testing results given by the two institutions mentioned aboveour slate contains no calcium. Water adsorption, fire endurance as well as weather resistance of our products are all meet the needs of class A standard. The slate can last more than 70 years without any color and shape changing. Our company owns 2.1966 square kilometers mining area and 4 mineral occurrences with abundant natural slate storage in Ziyang, where is famous for the best natural slate in China. The Ziyang Tiandi Natural Slate Co. Ltd. is equipped with the automatic flow process line and applying the most advanced underground mining technology. The annual output of our products including the slate roof tile, slate floor tile and slate dish, is more than 1 million square meters. Contact:Jia leiPhone: 86 15829232578, 86-029-89654733Web:en.tdslate.com