Pyrite is a rough grey stone with sparkly gold-like flecks. It has been sometimes called fool’s gold because of the resemblance to natural gold. The name comes from the ancient Greek word for fire. When rubbed with another metal, it can produce sparks which can be used to light a fire. This has been known since prehistoric times. In the 16th century, it was incorporated into muskets to ignite gun powder. It contains a rich content of sulfur and has been used in the manufacture of sulfur and sulfur compounds for centuries. As you can see from the pendant pictured above, it can be used as the focal point of a unique piece of jewelry.
You can see various stones set in silver pendants at Metal Jewelry Shaper