The 20 types of gemstones (described and with pictures)
A summary of the types of precious and semiprecious stones, explaining how to recognize them.
Rubies, sapphires, emeralds, diamonds, agates... there are many stones that decorate high-end jewelry and costume jewelry, associated with beauty, various meanings and even mystical powers.
There are many types of gemstones if we consider as such any mineral that seems beautiful to us at first glance, although in many cases they are actually semi-precious stones.
In the following we will go deeper into the types of gemstones that exist.What criteria are used to incorporate them in this group and we will also see other minerals of great beauty and hardness.
Characteristics of precious and semiprecious stones.
Precious and semi-precious stones are highly coveted items, especially in the world of jewelry. Due to their color, scarcity and beauty, gemstones are highly coveted in different are highly coveted in different fields, being the mainBeing the main business of jewelry, although we can also see them in electronics, making electronic devices, and also in alternative therapies, New Age movements and mystical beliefs.
Before finding out which are the main gemstones, it is worth clarifying that, although used interchangeably, the terms precious stone and gemstone are not the same, the terms precious stone and gemstone are not the same.. We understand gemstones as a broader group of minerals and similar substances that can be divided into two main groups: precious stones and semi-precious stones. For a mineral to be classified as a precious or semiprecious stone, it is necessary that it has the following properties.
1. Beauty
Precious and semiprecious gemstones are so because they have beauty, manifested in the form of unique colors, transparency, or luster.. Sometimes, to make a mineral into something beautiful, it is necessary to apply some kind of chemical that highlights some of its physical properties, a fundamental aspect in the jewelry industry.
2. Durability
Durability has to do with the stone's tenacity, that is, how difficult it is to scratch it with another stone, how difficult it is to scratch it with another mineral or how resistant it is to shocks and pressure.. You can also test the stone's resistance by applying chemicals to it and seeing how it stands the test of time.
Generally, the hardest stones, that is, those that are highest on the scale of hardness of stones are considered precious stones, being headed by the diamond.
3. Color
Color is considered, along with beauty, one of the fundamental characteristics for a gemstone to be considered precious or semi-precious. The most sought-after gems tend to be those with beautiful colors, such as green, red and blue, while the least coveted are white, transparent and black, except if they are white, transparent and black.while the least coveted are the white, transparent and black ones, except if they are diamonds that are seen as the most beautiful gemstone by many people.
4. Luster
Luster is the physical property that refers to how the stone reflects light on its faces.. In gemology, luster includes reflection, refraction, scattering and faceting of the light that strikes the stone.
The easier it is for the light to pass through the crystal, the better quality the stone is considered to be, while the more opaque the mineral is, the less valuable it is. The most brilliant stones are considered to be gemstones.
5. Rarity or scarcity
The scarcer a mineral is, the higher its price will be in the jewelry market. This scarcity may be due as much to the own scarcity of the mineral on the face of the earth as to the difficulty that supposes to be able to obtain it..
The pricipal types of precious stones
There are different ways to classify precious and semiprecious stones, mostly of mineral origin, although there are also those that come from living beings, as is the case of amber and pearls. Here we will focus on the two main categories into which we can divide them.
Varieties of precious stones
It may come as a surprise to many of you, but there are really only four types of pure precious stonesThe diamond, the ruby, the sapphire and the emerald. A few decades ago, amethyst was also included in this classification as a precious stone, but when huge deposits of this mineral were discovered in Brazil, its price decreased as it was no longer so rare and was considered a semi-precious stone.
1. Diamond
Diamond is the hardest known natural substance on the planet Earth, with a value of 10 on the Mohs scale.This is a striking property, but it is not the only one that makes it stand out from other stones, since this mineral also has the peculiarity of being made of a single element: carbon.
Although as a general rule we think of diamonds as transparent and white stones, the truth is that they can come in a wide spectrum of colors. Colored diamonds are called "fancy", being blue and pink the rarest, while yellow and brown are the most common.
2. Ruby
The name ruby comes from the Latin "ruber", which means red, alluding to its main physical characteristic. Its red color is intense and bright due to the metals that compose this mineral, iron and chromium..
Rubies belong to the corundum family along with sapphire, and has a hardness of 9 on the Mohs scale, making it the second hardest gemstone.
Normally, when extracted from nature this mineral presents a rough and unattractive appearance, but once it is worked on it becomes a highly valued gem in the jewelry market, adopting a radiant reddish tone.
3. Blue sapphire
The blue sapphire belongs to the corundum family, like the ruby and, in fact, it could be considered as rubies only with blue tones.. While it is true that there are sapphires of other shades, blue sapphires are the most coveted for their unique beauty and rarity.
Any corundum color other than red is called sapphire, which is why blue ones are accompanied by the adjective "blue" to distinguish them from others, which can be orange, pink, gray, black, brown, purple and green. Blue sapphire has the same hardness on the Mohs scale as ruby, 9.
4. Emerald
The name emerald comes from the Greek "smaragdos" which is believed to be a linguistic loan taken from some Semitic language in which that word must have literally meant "green stone", alluding to its striking color. This mineral belongs to the beryllium family and has a hardness of 8 on the Mohs scale.
Emeralds have always been highly valued because, despite the existence of other green stones, this one stands out for being a very crystalline mineral.. While other green crystalline stones are known today, none stand out as much as the emerald, with unparalleled colors and transparency.
Varieties of semi-precious stones.
Semi-precious stones are minerals, organic stones and mineraloids that have some characteristic that makes them beautiful. have some characteristics that make them beautiful, but not as beautiful as precious stones.. In addition, although they are rare substances, they occur in greater quantities in nature than diamonds, rubies, sapphires and emeralds.
The prices of semiprecious stones are very disparate, oscillating according to various conditions such as hardness, rarity and beauty. There are approximately 130 mineral species catalogued as semiprecious, in addition to amber and pearls, which as we have said are of organic origin. The most used in jewelry are the following.
1. Amethyst
As we have said before, amethyst was considered a precious stone some time agoBut after a significant amount of this mineral was discovered in mines in Brazil, it became a more common stone, making it part of the semi-precious stones.
But although it has lost value, it is still the most valued variety of quartz in the jewelry market due to its purplish lilac color, very appreciated as a gemstone. It can also be yellow or even transparent, depending on the amount of iron it contains. Its hardness on the Mohs scale is 7.
2. Agate
Agate is a variety of chalcedony, which can have various shades and colors, as well as being transparent, semi-transparent or opaque. Its physical characteristics are determined by the formation of silica microcrystals.. Its name comes from the Greek "Achates", the name given in Hellenistic antiquity to the Sicilian river Dirillo and has a hardness on the Mohs scale of 7.
The fact that its name is related to a river is no coincidence, since agates are formed by the action of subway waters that, being close to silicon saturations, fill rock cavities with this substance, as well as shells and bones. It is by this process that agates are formed with concentric bands, similar to the rings of tree trunks.
3. Aquamarine
Aquamarine belongs to the beryl family, like the emerald, and could be considered a variant of that gemstone only with a pale greenish blue tone.. Its name is due to its resemblance to the color and brightness of sea water. It has a hardness of 8 on the Mohs scale.
4. Alexandrite
Alexandrite is a very rare variety of chrysoberyl with a soft green or greenish-yellow color. The most relevant property of this semiprecious mineral is its ability to change shades and color when different beams of light strikes it, going from green to red.from green to red.
This stone was discovered in the time of Tsar Alexander II, which is why it is so called and also became a sort of patriotic symbol because this mineral has the same colors that had the flag of Imperial Russia. Its hardness on the Mohs scale is 8.
Amber
Amber or succinum is a stone of organic origin. Its most common name comes from Arabic and means "that which floats in the sea" since, in fact, amber floats in seawater. Its most common color is yellow, although there are also orange and reddish ones..
It is formed from fossilized plant resin, from conifers such as pine, which has hardened over time. Some very valuable pieces of amber may be sixty million years old or more, but no matter how old they are, they are usually quite soft minerals, with a hardness of 2.5 on the Mohs scale.
6. Aventurine
Also called aventurite quartz, aventurine has various shades of green, although it can have reddish, brown and yellow tones due to inclusions of other minerals. Its most appreciated visual characteristic, besides its color, is its inner sparkle when light falls on it.. It has a hardness of 7 on the Mohs scale.
7. Quartz
Quartz, also called rock crystal, has as main properties to emphasize its transparency and low cost.It is a mineral widely used in high costume jewelry as well as in jewelry.
It is formed from the slow crystallization of residual magmas and has a hardness of 7 on the Mohs scale.
8. Smoky quartz
The smoky quartz or fumé is a silica compound that has various shades of brown various shades of brown, from light to very dark, having a hardness of 7 on the Mohs scale.It has a hardness of 7 on the Mohs scale. It has a special variety of brown color which is called morrion.
9. Peridot
Peridot or olivine, once known as the gem of the sun, is composed of magnesium, iron and silicon. Its most popular color is olive green, although it is also found in other colors such as yellow, pistachio green and brown.. It has a very intense luster, is often found in volcanic rocks and has a hardness of 6.5 on the Mohs scale.
10. Garnet
Garnet has a dark reddish color, although it can also be found in other colors such as yellow, pistachio green and brown. can have orange, green, yellow, yellow and black tones.. It is a mineral belonging to the family of aluminum silicates combined with iron oxide and magnesium that give it its reddish garnet color.
Its cost is quite low because it is found in large proportions in nature, being a substitute for ruby for having a similar color but being much cheaper. Its hardness is 7.5 on the Mohs scale.
11. Topaz
Topaz is a semiprecious stone widely used in jewelry, both for its beauty and its hardness of 8 on the Mohs scale. It is found in blue, yellow, pink, smoky and smoky colors. the rarest and most quoted variety is the imperial topaz, of orange yellow and reddish color..
12. Turquoise
Turquoise is a greenish blue stone formed by alumina phosphate with a mixture of copper and iron.
Its name refers to the fact that it comes from Turkey, although in reality the Turks simply acted as intermediaries between Asia and the Middle East, where this mineral was extracted, and the West, where it arrived. It is a stone with the peculiarity of being porous, so it needs certain care.. It has a hardness of 5.5 on the Mohs scale.
13. Jasper
Jasper is a mineral belonging to the quartz or chalcedony family, but mixed with iron oxide. It is an opaque stone an opaque stone that can be found in different colors such as dark green, yellow or brown, being the most valuable the red or Blood jasper.. It has a hardness of 6.5 on the Mohs scale.
14. Opal
Opal is a very rare variety of quartz, which can be opaque or translucent. can be opaque or translucent and comes in different colors such as white, gray, blue, black or orange.. It has the property of having a play of colors in its interior, an effect that is due to the diffraction of light passing through its silicon microparticles, which project pure spectral colors. It has a hardness of 6 on the Mohs scale.
15. Lapis lazuli
Lapis lazuli is part of the silicates, mixed with lime sulfate and soda with small incrustations of pyrite and iron. It is a mineral of a very intense blue color, used to make necklaces and bracelets..
In the past it was a highly valued mineral and until the 19th century it was used as a pigment to obtain the blue color of oil paint. It has a hardness of 5.5 on the Mohs scale.
16. Onyx
Onyx is an opaque variety of agate, formed by striped quartz. It has dark and black colors, although there are also some with light and reddish tones.. The varieties of this mineral that are not black are known as sardonyx. Its name comes from the Greek "onyx" meaning "nail", a name associated with the Greek myth that when Cupid cut Venus' nails while she was sleeping, they fell to earth in the form of this mineral. It has a hardness of 7 on the Mohs scale.
(Updated at Apr 14 / 2024)