Have you ever seen a glittering diamond? If so, then you know the smile it brings to the face of admirers. This isn’t just true of diamonds; gemstones like emeralds, rubies and sapphires are all stones of different colors known for their brilliance and high prices. However, Mother Earth has provided us with many more jewels that are just as beautiful as those more famous varieties! This article will explore a few of these somewhat unknown beauties.
Before moving on, we should clarify the concept of carats. The purity and mass of gemstones and pearls are measured in a unit called carats. A carat is a unit of mass equivalent to 200 milligrams (0.2 grams) of the substance being measured. There are four basic parameters that govern the grading of all gemstones, commonly known as the four Cs of Connoisseurship: colour, clarity, cut and carat weight.
1. Blue Diamond: The most expensive gemstone
This article would be incomplete without the mention of the most expensive gemstone in the world. Yes, you heard that right… the most costly stone on the planet! A blue diamond is quite similar to a regular diamond, except for the additional element of color (blue) that leaves its observers spellbound. The gemstone owes this color to the small quantity of Boron present in its lattice structure. The Oppenheimer Blue became the most expensive jewel (per carat) ever sold at an auction in 2016. The 14.62-carat diamond cost its mystery buyer a whopping $50.6 million ($3.93 million per carat)
The Hope Diamond is another famous gemstone in this color category. First mined in India in the late 16th century, this rare stone travelled around the world before finally coming to rest in the National Museum of Natural History, USA.
Reference – Smithsonian Institution
The tourmaline family of gemstones consists of crystals that have a structure made of aluminium boron silicate (AlBoSio3). Within their core structure, metals such as manganese, iron, chromium and sodium are found, which impart the stones with various colors. Tourmaline stones come in many types, but watermelon tourmalines are perhaps the most interesting. The picture below quite clearly demonstrates where the name comes from!
Tourmalines are generally found among solidified deposits of molten magma near the veins that run closest to the core of the volcano and therefore experienced the highest temperatures. Another fun fact about these rare stones is that they might be magnetic. High concentrations of iron and manganese impart magnetic properties to some members of the tourmaline family. Now that’s what we call a multipurpose rock!