Thank you for submitting your item for appraisal. This appears to be a chinese serpentine rock mug of recent production. Serptentine, sometimes called "Suzhou jade", is a dense cryptocristalline mixture of serpentine group minerals, but not real jade. The mug´s body has been turned and carved from one piece of rock, the seperately carved handle is clued on with insulators. The estimate is based on similar items offered or sold at auction.