Question about Grundig Uc 6620

Absolutely no pearls or "soft to medium-hard" gemstones such as turquoise, opal, lapis lazuli, haematite, obsidian, apatite, fluorite, malachite, azurite or amber. It is unlikely that "harder, medium-hard" gemstones such as aquamarine, emerald, tourmaline, citrine, amethyst, onyx, garnet, quartz, etc. will remain harmless. Even "hard" gemstones such as topaz, ruby, sapphire or diamond harbour the risk that they are not pure but artificially filled, and the stones must not be glued in and gold-plated surfaces can become detached.