October birthstone - tourmaline

    Tourmaline has a variety of exciting colors. In fact, among all gemstone types, tourmaline has the widest range of colors, with almost different shades of color. Many of the names of tourmalines are inspired by their own colors: red tourmalines are the collective term for pink, red, magenta, orange-red or red-brown tourmalines, although some in the industry believe that the term does not apply to pink tourmaline. The color of the blue tourmaline includes indigo, blue or green-blue tourmalines. Paraiba is a rich indigo, green-blue or blue tourmaline from the state of Paraíba, Brazil. Chrome tourmaline is dark green. Regardless of its name, its color causes are mostly due to the presence of vanadium, which is also common in Brazilian and African emeralds. Multicolor tourmalines have more than one color. The most common combination is green and pink, but it can also be a combination of other colors.

     The color of the tourmaline has many different causes. It is generally believed that trace element iron (and possibly titanium) produces green and blue. Manganese produces red and pink and may produce yellow. Some of the shades of pink and yellow sodium lithium tourmaline may be due to the color center of the radiation. Some of this phenomenon is naturally occurring, and some are artificially made in the laboratory. Let's take a look at the history and knowledge of Tourmaline. This 376.85-carat tourmaline is crafted by O. Hansen, and the design uses the colors of the tourmaline. 

  In the 16th century in Brazil, the Spanish conquistador washed away the dirt on the green tourmaline crystal, but confused this bright gem with the emerald. His confusion persisted until scientists confirmed the family gemstone necklace as a different mineral species in the 19th century. The confusion about this type of gem is even reflected in its name, which comes from toramalli, which means “mixed gemstones”.

     The striking cat's eye tourmaline gemstones are produced in Brazil. The inclusions bring a cat's eye effect and increase its value. As long as the color is rich and attractive, dealers often ignore some of the visible inclusions contained in the red tourmaline. The inclusions that touch the surface can affect the luster and finish of the gemstone and are difficult to sell. In addition, although liquid inclusions are not readily detectable in intensely colored gemstones, gemstones are not popular if they contain significant white inclusions, no matter how brightly colored they are. The inclusions have higher visibility in gemstones of light and low chroma. Since these gemstones do not have rich and attractive colors to compensate for the inclusions, most buyers refuse to purchase such gemstones with visible inclusions. Many brightly colored, intrinsic tourmalines will be cut into a convex surface to highlight the color and dilute the inclusions. For pink and red solid gold jewelry, inclusions that are visible to the naked eye are common. Unless the size or quantity of the inclusions affects the appearance, consumers who are knowledgeable generally regard color as the primary value factor.  getnamenecklace It is expected that green tourmalines will not contain visible inclusions, so visible inclusions may reduce the value of green gemstones. For other colors, tourmaline, which contains no visible inclusions, is more valuable than tourmaline containing macroscopic inclusions. The more obvious the inclusions, the lower the value. The slender shape of many of the tourmaline crystals has a direct impact on the shape and proportion of the finished gemstone. Therefore, there are many narrow, non-standard size tourmalines on the market. While some of the tourmalines are very attractive, many gemstone buyers prefer standard-size gemstones because they are easier to handle in standard inlays. Jewelry designers use custom inlays to fit the shape of the finished tourmaline.

     The cutter usually shapes the tourmaline into a rectangle. Cutting parallel to the length of the rough crystal helps to reduce losses. But the cutter must also consider the optical properties of the tourmaline. Tourmaline has a strong polychromaticity, which means it has different colors in different crystal directions. Tourmaline has a strong polychromaticity, which means it has different colors in different crystal directions. One of the tourmaline multicolor colors is usually much darker than the other colors. In addition, many popular jewelry absorb more light along the length of the crystal than light that is absorbed perpendicular to the length. So, when you look at the gemstone along the length, it will appear dark green, even black; when viewed perpendicular to the length, it will appear pale green.

Source:www.getnamenecklace.com

    Many cutters process gems according to their color depth, rather than taking a longitudinal cut. In order to deepen the color of the light rough stone, they will make the table top direction of the stone perpendicular to the length of the crystal. In order to make the dark rough look brighter, the cutter cuts the tabletop of the stone parallel to the length of the crystal. The higher the carat weight, the greater the price per carat. Although there are huge samples, this is a minority. The supply of rough stone materials suitable for facets has declined, causing prices to rise sharply. For finished gems with similar color and clarity, 5 carats is the price inflection point. More than 5 carats, the price per carat usually increases dramatically. Larger tourmalines are often crafted into unique jewels by gemstone sculptors to satisfy customers' desire to be different. The well-known Idar-Oberstein gemstone cutter Bernd Munsteiner gives this 11.18-carat blue-green gemstone a unique style.

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