This is a nice example of a Stromatolite cabochon. Although often marketed as Jasper, it is indeed Stromatolite. This is incredibly intricate, with swirls of beige and various browns.
A simple definition of Stromatolite is that it is a laminated rock formed by the growth of blue-green algae. Stromatolites are not only Earth's oldest fossils, but are intriguing in that they are our singular visual portal into our early past on earth - the emergence of life, and the evolving of the beautiful forms of life of modern time. A single small piece of stromatolite has encoded biological activity perhaps spanning thousands of years. Stromatolites are fossil evidence of the prokaryotic life that remains today, the preponderance of biomass in our biosphere.
This sample is good for those interested in collecting the many forms of Agate, Jasper, or sometimes other minerals, or for those interested in pendant jewelry.