The range of white to grey to black in these marquis-cut orbicular jasper stones is framed in shiny silver. It almost looks like someone turned the saturation down on a more colorful stone for a dramatic, greyscale look.
sterling silver, orbicular jasper
Jasper, like agate, is a very common variety of chalcedony. Unlike agate, jasper is opaque. There are many different types with many colors and patterns. This kind is usually referred to as orbicular jasper.
Each of the dot-like shapes you see in orbicular jasper is a cross-section of a little sphere, which formed as a crystal bubble. This kind of stone is found all over the world, but most typically in coastal areas, where the orbs formed under water.