Erica arborea of the family Ericaceae. A favorite wood of pipe manufacturers. I have not seen this shown as anything but a burl, so I assume it's from a plant that does not produce wood of a sufficient size for lumber or veneer. Areas of growth include Africa, Mediterranean region, Southern Europe).
my samples: NOTE: these pics were all taken in very bright incandescent lighting ("soft white" at 2700K) colors will vary under other lighting conditions
burls listed specifically as briar / Erica arborea