925 Sterling Silver:
925 Sterling Silver is a combination of 92.5% pure silver and 7.5% of another metal, and it is the highest percentage of fine silver possible for jewelry subject to everyday wear. Fine silver (99.9% pure) is generally too soft and malleable for jewelry. Therefore, it is usually combined with copper to give it strength, while at the same time preserving both the ductility and beauty of its original form.
Stone or rock, is a naturally occurring solid aggregate of one or more minerals or mineraloids. They have been used by mankind throughout history. From the Stone Age, stones have been used for tools. The minerals and metals found in stones have been essential to human civilization.