Highly-coveted sulphide marbles get their name from the figure inside that looks like it’s made out of sulfur. Largely manufactured in German cottage industries from the mid-19th to the early 20th century, the tiny figures are actually made of porcelain clay. Animal sulphides are the most common type. People, numbers, or angels, like the one pictured here from the Larry and Cathy Svacina Collection, are harder to find.

Because antique sulphides were handmade, it’s not uncommon to find flawed or off-centered figures. Others have trapped air bubbles or pontil marks. While some collectors may seek out these imperfect gems, others believe they are, as these heavenly hosts say, “no good.”