World’s largest faceted gemstone ?
The precious stone is a mineral crystal, which is used in its cut and polished form in the making of jewellery or other decoration (also known as gem, precious gem, half precious stones). However, some rocks (such as lapis lazuli and opal) and organic materials that are not minerals (such as amber, jet, and pearl) are often used for jewellery and are thus often called gemstones. Although most gemstones are hard, some soft minerals are used in jewellery because of their lustre or other physical properties with aesthetic value. Another factor that contributes to the value of a gemstone is its scarcity. Apart from jewellery, engraved gems and hardstone carvings, such as cups, were major luxury art forms from antiquity.
A gem maker is known as a lapidary or gemcutter, and a diamond cutter is known as a diamantaire. The traditional Western classification, which dates back to the ancient Greeks, starts with a distinction between precious and semi-precious stones; other cultures make similar distinctions. Diamond, ruby, sapphire, and emerald are considered precious stones in contemporary usage, while all other gemstones are considered semi-precious. This difference reflects the rarity of the respective stones in ancient times, as well as their quality: all are translucent with fine colour in their purest forms, except for the colourless diamond, and very hard, with hardnesses ranging from 8 to 10 on the Mohs scale.
Other stones are classified based on their colour, translucency, and hardness. There is no internationally agreed grading system for gemstones. The Gemological Institute of America (GIA) developed a system for grading diamonds in the early 1950s. Historically, all gemstones were graded by sight. The introduction of 10x magnification as the standard for grading clarity as part of the GIA system was a significant innovation. Other gemstones are still graded by sight (assuming 20/20 vision).
Amazing facts about gemstones
- Amber is the earth’s softest and lightest gemstone. Because it is so light, it floats in salt water. It’s a stone made from the sap and resin of fossilised prehistoric trees. The fossilised sap must be at least 30 million years old in order to be considered amber. The majority of amber jewellery is made of Baltic amber, which is known to be the most durable.
- The diamond is the hardest gemstone. A diamond can only be scratched by another diamond. It has a Mohs hardness of 10 on the Mohs scale for gemstones, which means it is as hard as a gemstone can be. This is why diamonds are appropriate for everyday wear in an engagement ring because they are not easily damaged.
- The world’s largest faceted gemstone is a record-holding topaz discovered in Brazil that weighs nearly 37,000 carats.
- Green gemstones were treasured and cherished by the ancient Egyptians. It is thought that at the time, people found it difficult to distinguish between the two beautiful green stones, emerald and peridot, and occasionally mistook one for the other. Peridot was a favourite of Cleopatra. Although she adored emeralds, because they can appear similar, she may have been inadvertently decorated with emeralds as well as her favourite.
- Consider how many beautiful pearls are worn by jewellery lovers all over the world. Each of those pearls took between a year and three years to mature. A small piece of shell or a bead, known as the nucleus, is planted inside the mollusk in order for it to develop into a beautiful pearl. These pearls are then harvested after a couple of years, when they have grown to the ideal size for a beautiful piece of pearl jewellery.
- Both the opal and the tourmaline are the most vivid gemstones. Because tourmaline is the only gem that can come in every colour, it is also known as the “Rainbow Gem.” The opal is a colourful stone as well, but some opals are colourless. Opals may have colour flashes within their black or white background.
- The Cullinan Diamond, weighing 3,106.75 carats (621.35 g) and discovered on January 26, 1905, at the Premier No.2 mine in Cullinan, South Africa, was the largest gem-quality rough diamond ever discovered. The mine’s chairman, Thomas Cullinan, inspired its name. It was put up for sale in London in April 1905, but despite widespread interest, it remained unsold two years later. The Transvaal Colony government purchased the Cullinan in 1907 and presented it to Edward VII, King of the United Kingdom, who had it cut by Amsterdam’s Joseph Asscher & Co.
- Black Onyx is not a natural gemstone; rather, it has been dyed black. As a result, it should be cleaned very carefully with moderate clearness to avoid exposing the brown and orange Sardonyx.
- A very rare and unique type of gemstone can only be found and formed in the fossils of extinct cephalopod species over the course of hundreds of millions of years. One of them is an opalized fossil worth more than $1,000,000.
- Amethyst was once considered a precious gem, but after scientists discovered large reserves of it in Brazil, its price fell and it is now considered a semi-precious gem.
- Gemstones are classified into three types: treasured gemstones, semi-precious gemstones, and organic gemstones.
- Ammolite is an opal-like gemstone that comes in an infinite number of colours and is one of the few biogenic gemstones known. It is made up of fossilised Ammonite shells (a pre-historic squid-like creature).