Yellow precious, semi-precious and decorative stones symbolise light, warmth and abundance.
Such minerals are recommended for calmness, spiritual recharging and getting rid of depression. Medical and healing powers are ascribed to many yellow stones. Their beauty is an obvious quality: lemon yellow, orangey-yellow, golden and slightly brownish crystals are widely used in the jewellery world. They have a high value and are appreciated by many people. In this blog post, we want to introduce you to the most common and popular yellow stones in the jewellery industry.
Only one diamond out of a hundred thousand has a yellow hue. The hue can be faint, like a very watery yellow, or as vibrant as a bright-lemon colour. It can also be orangey like a mandarin, or golden-brown, like cognac. Such colouring depends on the amount of lithium in the stone. The higher the lithium content, the more intense the colour is, and the higher the value of the diamond.
Coloured diamonds are very expensive – take for example Sancy, once the biggest yellow diamonds known to people (even though very very pale yellow, as can be seen on the picture bellow). In the 1570s, it made its owner, Nicolas de Harlay, seigneur de Sancy, a very rich man. But even today’s world, the prices on such diamonds are crazy: in 2013, an orange diamond weighed at 14.82 carats was sold at an auction for an almost mythical price of 35.5 million dollars.
Sapphires (a type of the mineral corundum) can have many different colours, even though this precious stone is mostly popular for its usual deep blue hue. Yellow sapphire is the rarer example of the mineral. The shade ranges from lemon to amber, and the colouring of the stone itself is very often not consistent over the whole, it can shift to a different shade under varying light, or it can have streaks of darker hues.
The most precious sapphires have an even yellow tone, with no highlights or impregnations. Some samples get unlucky due to their pale colouring and get written off as colourless. The average size of yellow sapphires does not exceed 8-10 carats. The deposits of these minerals can be found in Burma, Shri-Lanka, Madagascar and Afghanistan.
As a relatively cheap precious stone, topaz is mined worldwide and is very popular in the jewellery-making industry. The appearance of the yellow variety of topaz is quite similar to citrine or smoky quartz. Yellow is the most frequent naturally-occurring hue for this semi-precious stone, while green, red, blue or purple topazes are much less common.
Heat treatment can change the colour of topaz. Yellow topaz can be turned into a pink or a green one. Mining is conducted in countries of South and North America.
As seen with most other stones, impurities determine the hue of tourmaline, too. Pink and raspberry is the most prevalent colour in tourmaline, while blue and yellow are the rarest. Depending on the colour and the transparency of the gem, tourmaline is classified as semi-precious or “to be used for tool-making”. Polychrome tourmaline, also known as watermelon tourmaline, can have a yellow, raspberry and green hue at the same time, or shift colours depending on lighting. This is the most valued tourmaline, receiving prices as high as $600 per carat. It is definitely a stone to have in your collection of jewellery.
Dravite is the name given to yellow tourmaline, and its hue varies from pale yellow to a darker brown tint. In addition to the basic overall yellow hue, the gem can have an alexandrite effect or a "cat's-eye" effect, making the stone look mysterious and exotic.
A variety of quartz, this stone has a sunny golden hue. It is extremely hard, making it easier to process, shape and cut. The yellow colour is given to this stone by iron impurities, which can influence the shade to be as light as pale-lemony and as bright as saturated orange. Dark orange crystals are called “Madera”, and have the highest amount of iron in them.
Yellow quartz is less common than clear and is therefore valued higher.
Most of the mining is done in Brazil, but the stone is also known to be found in the north of Russia, Canada, and France. Specific tinting of the gemstones can also be achieved artificially through heat treatment: under the stimulus of high temperatures, amethyst and smoky quartz can acquire a golden or brown hue.
Natural zircon (not to be confused with cubic zirconia, pictured below) is an absolutely translucent crystal with a strong diamond-like glitter, also sometimes called “jargoon” or “jargon”. Some of these stones, however, have a yellow or red tint. Also, through heat treatment, the stones can acquire a rich turquoise hue (starlit), green, or deep red (hyacinth).
Mining occurs in countries like Thailand, Norway, and Madagascar. In places like Russia and Canada, zircon can also be found in and around mountain ranges. The stone is fragile, a quality not ideal for jewellery-making, and as a result yellow zircon is not often seen in typical jewellery.
Heliodor (yellow beryl)
Heliodor is a type of beryl, and is recognised by the pleasantly warm yellow shades and high transparency. When translated from Greek, Heliodorus literally means "gift of the sun". It is no wonder, then, that the precious stone is so warm and sun-like. This hue is given to the crystals by iron impurities (as has been seen in other cases). The most valuable heliodors are of a rich yellow or amber tint; greyish, white or overly pale gems are less valued.
Heliodor visually resembles other gemstones such as citrine (yellow quartz) or yellow topaz. If heat treated, yellow beryl acquires bluish tones or becomes completely transparent. In jewellery-making, heliodor is used in its natural yellowish hue. Stones of bleak colours, which are too pale or have a greyish tint, are the ones that get treated.
Apatite – a mineral of phosphate –comes in many different colours: yellow, purple, blue, and green. Yellow apatites are extremely sparkly and can be completely clear or very opaque, depending on their structure and the presence of other minerals. In jewellery pieces, yellow or blue stones, which have a pure diamond-like sparkle, are most often used.
Mining sites are all over the world, with places like Burma, North America, Italy, and Sri Lanka being the most common suppliers. The weight of the gems is usually less than 5 carats, however, examples weighing at 15–20 carats do exist.
This stone is not typically used for jewellery, but rather serves as tool-making material. It is easy to access due to its wise distribution, and has qualities which make it less appealing aesthetically, but desirable for durability – for example, it is resistant to acids. The structure of the stone is layered; the colour is uneven over the whole gem, with many other-coloured streaks and highlights. To be used in the jewellery industry, the stone has to be grown artificially. The yellow colour of the crystal is achieved by the mixing in of iron oxides.
Natural agate is a solid mineral with glass-like sparkle after polishing. The shades of yellow exhibited by the stone are quite diverse – from very light to a deep dark-brown.
This mineral is a subclass of sulphide, and is also known as zinc blende. When the colour of the gem is lemon, it is called a “honey blende” or “honey sphalerite”, whereas darker orange-red shades are called “ruby jack” or “ruby blende”. It is a very fragile stone, one that is almost never used for jewellery due to the complexity of the cutting process with such frail material. The rare precious stones that are suitable for processing and subsequent insertion into jewellery are mined in Spain and Mexico.
Amber is fossilized tree resin, and is distributed and popular all around the world. It has a bright, sunny hue, high transparency and slightly dulled shine. Synthetic amber, which is made of various artificial resins, is identical to the natural stone to the naked eye. Under closer inspection, however, some minor differences can be seen.
In addition to yellow shades, amber can be of colours such as fiery-orange, green, white, black, and cherry. There even is a unique hue of amber, blue. The cost and value vary depending on the weight and shape of the stone, the colour, transparency and the presence of impurities.