The term cardinal gemstone was traditionally used to refer to gemstones that were valued above all others. The five gemstones referred to as the cardinal gems included diamond, sapphire, ruby, emerald, and amethyst. The important use of these gemstones in traditional religious and cultural ceremonies and other events aided in labeling them as the cardinal gems. However, with the discovery of newer gemstones and new deposits of the cardinal gems in recent times, the term cardinal gems has largely fallen out of use. The traditional cardinal gems are as follows:
5. Diamond -
The most coveted gemstone, the diamond, is one of the five cardinal gemstones. It is a solid form of carbon and is regarded to be the hardest of any bulk material. It also has the highest thermal conductivity. Both these properties make it an ideal choice for major industrial applications like tool cutting and polishing. Diamond is one of the purest chemicals as its rigid lattice structure hardly allows any contaminants to enter. Most of the natural diamonds recovered and in use today were formed billions of years ago at extreme conditions at great depths under the surface of the Earth. Diamond jewelry is one of the most expensive forms of jewelry in the market.
4. Sapphire -
Sapphire is one of the five cardinal gems. This precious gemstone is a variety of corundum. The latter is a mineral primarily composed of aluminum oxide with traces of other chemicals like iron, chromium, vanadium, etc. Sapphire has a typical blue color but occasionally, sapphires of other colors like green, orange, yellow, etc., have also been uncovered. A sapphire never has a red color since a red colored corundum is always a ruby. Sapphires occur in the natural form and are also synthesized in the laboratory. The crude stone discovered during mining operations is subjected to cutting and polishing to yield gem-quality sapphire. The gemstone is often worn as jewelry. Due to the fact that it is one of the hardest minerals, sapphires are also used to manufacture wristwatch crystals, movement bearings, electronic wafers, etc. The Star of Asia Star Sapphire, the Star of Bombay, the Stuart Sapphire are some world famous sapphires.
3. Ruby -
Also a variety of the corundum mineral, a ruby is red in color due to the presence of the trace element chromium in relatively large quantity in the mineral. Rubies are of different qualities. The cut, color, and clarity of the gemstone determine its quality. Traditionally, rubies of ‘blood red’ or ‘pigeon blood’ color are deemed to be of top quality. The Sunrise Ruby is regarded as the most valuable ruby in the world. Myanmar’ Mogok Valley is famous for ruby mining activities since some of the most exceptional rubies in the world were discovered here.
2. Emerald -
Another one of the five cardinal gemstones, the emerald, is a variety of the mineral beryl. The main component of the mineral is Be3Al2(SiO3)6. Trace amounts of chromium and occasionally, vanadium is also present in this mineral. Emeralds are characterized by their green color. To be labeled as a top gem, an emerald must have a pure verdant green hue and also exhibit a high level of transparency. In ancient times, Egypt, India, and Austria were important emerald mining sites. Today, however, Colombia is regarded as the world’s top producer of this gemstone. The Chalk Emerald, the Mogul Mughal Emerald, etc., are some of the world famous emeralds.
1. Amethyst -
Another cardinal gemstone, the amethyst is a variety of quartz that is famous for its violet color. In the ancient times, it was believed that this stone could protect its owner from drunkenness. Hence, the Greeks wore the stone as jewelry and even drank from drinking vessels carved out of amethyst. The best quality amethyst has been discovered in Brazil, Sri Lanka, and Siberia. Amethyst was originally one of the most valuable gemstones till the discovery of large deposits of this stone in some parts of Brazil. Thus, its current classification as one of the cardinal gems is debatable.