Thank you for submitting your item for appraisal. This appears to be a mid 20th century chinese prehnite carving depicting four birds sitting on a branch. The carving is very detailed and variations in the colour were integrated into the carving, e.g. brown flowers or the bird´s tail. Prehnite is easier to carve than jade and quite common in China. The estimate is based on recent auction results. "Asking prices" in the trade can be higher and vary. There is no measurement for the sentimental value you might attach to it. If it was jadeite the value would be approximately 800-1000 USD.