This stone is also known as crocodile jasper despite not actually being a jasper. Many colourful patterned stones used for decorative purposes are given trade names. In many cases they're labelled as jasper because it's a name people are familiar with. All too often it's not an accurate description of what the material is.
There is a small firescale mark in the sterling silver setting which can be seen in our second photo. These marks occur whilst silver is being worked on at very high temperatures. For this reason this piece has been slightly reduced.