Stibnite is a mineral composed of antimony sulfide, with the chemical formula Sb2S3. It typically appears as a gray or black, metallic-looking crystal and is often found in hydrothermal veins. Stibnite is primarily mined for its antimony content, which is used in various applications, including flame retardants and batteries. This mineral has a layered structure, which can make it fragile and easy to break. Stibnite is also known for its unique, elongated crystal formations, which can resemble sword-like shapes. Due to its properties, it has been of interest in both industrial and scientific fields.