Vintage Sterling silver earrings with Marcasite and what is either Onyx or Obsidian stone. Has 925 stamp on back of each, post back, unique design. From experience 80s/90s Marcasite jewelry is usually paired with Onyx or Obsidian. The black stone sounds like glass and has faint brownish inclusions on the back of one earring which makes me think it's obsidian but that's just my opinion. These are really cool no matter what stone it is and very unique. All the Marcasite stones are intact and sparkly. Measures 1.5 inches long and half inch wide.