Metal detectorists in Wales have unearthed nine priceless valuables dating to the medieval and post-medieval periods, including a gold ring decorated with a spooky-looking skull crafted from white enamel.

After analyzing the curios, Graeme David Hughes, the senior coroner for South Wales Central in the United Kingdom, officially declared them to be “treasures,” a term that refers to bonafide, often metal artifacts that meet a specific archaeological criteria, according to the U.K.’s Portable Antiquities Scheme.