Diamonds and precious minerals

Diamonds are on exhibit in their mineral state to show how the king of gemstones is naturally formed, and what the crystals look like. A real 10-carat class diamond is also on display in exhibit Room 4, with other two large-sized diamonds. In the adjoining showcase are other precious stones, with the cut stones exhibited in pairs with their respective mineral counterparts. The charm of many of the stones lies in their unique colors. The colors of gem minerals are generated by three different mechanisms. Some of the gem minerals, exemplified by peridot and garnet, are the natural colors of the minerals themselves. The other type of gem colors is due to small amount of metallic elements that are present as impurities in essentially colorless minerals. A special type of crystal defect called color centers gives rise to beautiful colors in some of the essentially colorless minerals: a good example is imperial topaz.