The texture of sulfur depends upon the form that it takes, and it may be powdery, bumpy or smooth. Sulfur is a relatively common substance on Earth, and it is an important component of a number of geochemical and biological processes. Humans utilize sulfur for a variety of commercial applications, including matches, pyrotechnics and fertilizers.
Sulfur most often occurs as a thin dusty covering on other objects. In this form, the texture of the element is powdery. At other times, sulfur occurs in crystal form. Crystallized sulfur may have a smooth or bumpy texture, depending on its age, impurities and the circumstances surrounding its origin. Sulfur is a brittle crystal, and it has limited commercial applications. However, it has medium hardness, so it resists crushing better than it resists a striking blow. Pennies will easily scratch sulfur. Sulfur is opaque, meaning that no light will penetrate it.
Sulfur is most often produced volcanically, but it is also produced by biological systems. Occasionally, sulfur forms ribbons through the bedrock of the Earth. Naturally occurring sulfur often contains traces of selenium or tellurium. Sulfur has been well known throughout history for its unpleasant smell, which is said to resemble rotten or old eggs.