Thank you for submitting your item for appraisal. This appears to be a basalt conglomerate stone carving .I could not locate anything similar in museum collections. The facial features, the hairstyle, the collar etc. don´t fit to any culture of that region, the parallel scratches at the bottom appear to be traces of modern machinery. Unless proven otherwise I would consider this a modern artefact. In addition the new cultural relics protection laws would require you to have official papers from Costa Rica to be able to legally sell it. The estimate is for a modern decorative stone carving.