Gemstone trees from Peru (including Manganocalcite, Opal, Chrysocolla, etc.)

Gemstones are rare minerals that are often used in jewelry and decorative objects. The characteristics of gemstones include beauty, such as color, luster, fire, transparency and lighting effects; durability, assessed for hardness, fragility/splittability and chemical resistance; and rarity, based on how often they occur in nature. Gemstones can be cut in different ways, the basic distinction being the cabochon, a convex cut, and faceted, where the surface of the gemstone is cut into multiple facets. During the grinding process, properties such as color, color distribution, inclusions, special lighting effects, dispersion and fracture and cutting surfaces are taken into consideration. They are transformed into necklaces, earrings, bracelets and other jewelry, but they also find industrial applications. Well-known gemstones include diamond, ruby, emerald, sapphire, aquamarine, topaz, tourmaline, amethyst, citrine, carnelian, opal, onyx, turquoise, lapis lazuli and garnet. In the 18th and early 19th centuries it was fashionable to make jewelry with someone's name or initials incorporated into it. Gemstones were chosen based on the first letter of their name, which led to the gemstone alphabet. In the 19th century, acrostic jewelry was also made, expressing feelings with gemstones. The best-known example is the English 'regard' ring, an engagement ring in which the word 'regard' was formed by the gemstones ruby, emerald, garnet, amethyst and diamond.