Precious Stones
Precious stones and semi-precious stones are actually pieces of mineral crystal that many of us use different types of according to our interest or need. These precious stones have played a special role in people's lives throughout history; Gems and stones have also been used as ornaments or to decorate items and objects, dress and hair, architectural decorations, etc. Apart from the beauty and brilliance of these precious stones, their rarity and uniqueness made them imagine superhuman and magical powers. This group of stones has a very high value due to their hardness and rarity and is much more expensive compared to the group of semi-precious stones. In general, high-quality diamonds, green emeralds, red rubies, sapphires, or any rare mineral are known as precious stones in the jewelry industry.
semi -precious stones
Any other precious stone other than 4 precious stones (diamond, emerald, ruby, sapphire) is considered semi-precious. Some of the most famous stones are alexandrite, opal, amethyst, aquamarine, garnet, lapis lazuli, citrine, moonstone, tiger's eye, topaz, turquoise, pearl, tourmaline, tanzanite, rose quartz, etc. The division of such stones into the semi-precious group has more of a commercial basis and does not mean that the value of each precious stone is higher than the semi-precious stones. A set of semi-precious stones are those that are valued for their beauty and are available in the price range from cheap to expensive depending on their purity and quality.
Agate Stone
Agate stones are formed by the precipitation of silica in underground water in the cavities in igneous volcanic rocks. These solutions are formed by the crystallization of silicate phases in the cooling magma and the accumulation of silica in the cavity of the lava rocks. The larger the holes of the host, the greater the chance of producing this gem in larger sizes. These deposited materials sometimes form a thin sequence of dense and circular silica layers around the walls of the cavity, and sometimes these layers form flat layers from the bottom of the cavity upwards. These layered structures are one of the characteristics of this gem stone, which can be seen in different colors due to the presence of impurities in the mentioned solution.
variety of colors in agate
This colorful gem can be seen in more than 30 different colors in nature. Due to the quality of color and the phenomena it shows, this mineral is among semi-precious stones. A wide range of colors such as white, gray, brown, red, pink and even black can be seen in them. Among the main factors affecting its color, we can mention their microscopic structure, the presence of liquid, solid, gas inclusions, and especially the presence of color-forming metal elements such as iron, chromium, copper, titanium, manganese, cobalt, and nickel. /p>