Ying Stone is a type of sedimentary rock classified as limestone, primarily quarried from the mountainous terrain of Yingde, located along the middle reaches of the Bei River in Guangdong Province. The region features a well-developed karst topography, where the bedrock is highly susceptible to dissolution and weathering, resulting in rugged, convoluted formations. Furthermore, the area is characterized by abundant sunshine and rainfall, as well as extreme temperature fluctuations; these conditions cause the rock faces to fracture and tumble into the valleys below. Once exposed to the corrosive effects of the acidic soil, the stones acquire a distinctive appearance-hollowed-out and intricately perforated. While the natural color of Ying Stone is white, weathering and the presence of mineral impurities (such as copper and iron) give rise to a diverse palette, including black, bluish-gray, dark gray, and pale green. Black and bluish-gray are the most common hues, with a deep, lustrous black-resembling lacquer-being the most highly prized; these stones are often interspersed with veins of white calcite.
The stone is hard yet brittle; high-quality specimens emit a resonant, metallic ring when struck. While the texture of most Ying Stones tends to be dry and coarse, those possessing a slightly moist, lustrous quality are considered particularly valuable. The contours of Ying Stone are highly variable, frequently featuring "peep-holes" or "stone eyes" that lend the pieces an intricate, sinuous elegance. The surface is characterized by deep, dense folds-making it the most prominent example of the "wrinkled" aesthetic among ornamental stones. These surface textures manifest in various forms-such as "sugarcane residue," "honeycomb," "large folds," and "fine wrinkles"-creating a look that is both exquisite and richly varied. Typically, there is a distinct difference between the front and back of the stone: the front presents a dynamic, undulating topography of peaks and hollows, while the back remains relatively flat and unremarkable.
