BEAUTIFUL CHECKERBOARD CUT NATURAL GREEN PERIDOT. 1.10CT. 8MM TRILLION STONES. 6-7 ON THE HARDNESS SCALE . THIS IS THE BIRTHSTONE FOR AUGUST. I HAVE LISTED 1 9MM ROUND MATCHING STONE ON MY WEBSITE IF YOU ARE LOOKING TO MAKE A SET. NEVER CLEAN PERIDOT WITH STEAM OR ULTRASONICS. YOU MAY BUY ONE STONE OR BOTH.