2 New Gem Jars Gemstone Display For Jewelry Showcases & Countertops. This is a new set of 2 white gemstone display tray inserts. This insert contains 15 removable clear plastic round jars. These will hold all of your loose stones, beads and coins. Each gem jar comes with a white insert pad inside and lid. The inside diameter of each gem jar measures approximately 1" (25 mm). Each insert measures approximately 7 3/4" x 4 1/4" x 3/4" (197 x 108 x 19 mm).