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Why Quartz is King

29th November 2023. By Sarah Hardy

Quartz is a versatile stone that occurs in a variety of colours, formations, and localities. It is a hard stone, with a remarkable property: the ability to vibrate at a precise frequency. This has led to its use in science engineering and technology but is probably most well-known in some of its common gem varieties, often found in jewellery.

It can be found in enormous crystals, sometimes cut in half, and displayed as geodes (the likes of which can occasionally be found in our Natural History and Taxidermy Sales) and in tiny waterworn pebbles. It has been found and mined across the world, such as the cut quartz gems from Scotland, which are known as Cairngorms.

Crystalline quartz with no impurities present is clear and known as rock crystal. Different impurities or inclusions give it assorted colours or appearances. Purple quartz gemstones are called amethyst, yellow quartz is citrine and brown stones are smoky quartz. Polycrystalline quartz gives us agates such as jasper, bloodstone, cornelian, sardonyx and simply, banded agate, which is commonly found as large slabs in works of art and sometimes set into pieces of furniture.

Quartz carried the “semi-precious” moniker for a large part of the 20th century, probably due to its prolific nature and inexpensive price tag. However, good quality gem quartz should not be undervalued. It can have a mesmerising quality due to its vitreous lustre, as seen in a well-polished cabochon smoky quartz in our upcoming Jewellery, Watches and Silver Sale on 13th January. Neatly topped with a seed pearl set coronet it is a fascinating gem: the way the light moves through the stone and the slight colour variances depending on the angle it is viewed from makes it hard to put down.


A Smoky Quartz Pendant on Chain

Estimate: £200-300 plus buyer’s premium


As well as its myriad of uses in industry, quartz is versatile in its gemstone form. A beautiful example of cabochon amethysts can be seen in a pair of drop earrings, the pear-shaped amethysts suspended from trefoils of seed pearls, so delicately presented, typical of the early 20th century. In this example the amethysts are in closed back settings, with a foil backing. This technique was used with paler stones, to give a stronger hue or depth of colour.


A Pair of Amethyst and Split Pearl Drop Earrings

Estimate: £150-200 plus buyer’s premium


Quartz gemstones have commonly been set with other gemstones, either as an assortment of colour, shape and size as in some Arts & Crafts jewellery, or as toning colours as seen in the necklace below. This wonderful example of early 20th century jewellery is set with yellow topaz throughout and a citrine pendant from the base. Whether this was a deliberate choice, an error, or the citrine is a replacement due to damage is impossible to be certain about, but the appeal of the object cannot be in doubt.


A Citrine and Topaz Necklace

Estimate: £500-700 plus buyer’s premium


The versatility of a cut and polished amethyst can be seen in the two following rings. The first ring showcases an amethyst in a modernist bark effect setting (hallmarked 1973), this chunky mount and textured finish gives an interesting stage for the amethyst to sit on. In contrast, a more traditional style in the latter ring gives the amethyst a delicate surround of diamonds. The difference between the settings creating a very different look for this beautiful stone.


An 18 Carat Gold Amethyst and Diamond Ring

Estimate: £250-300 plus buyer’s premium



An 18 Carat Gold Amethyst and Diamond Cluster Ring

Estimate: £600-800 plus buyer’s premium


One last piece of jewellery for consideration is a banded agate pendant. Agates in jewellery offer interest from their individual band spacing and curvature, and many hues within the stone, creating a very wearable attractive piece.


An 18 Carat Gold Agate and Diamond Pendant on Chain

Estimate: £250-350 plus buyer’s premium


In conclusion, the wide variety of uses, from transmitting radio signals, to ensuring a watch keeps accurate time, to simply being aesthetically pleasing in anything from home furnishings through to jewellery must surely make quartz worthy of Royal status: Quartz is King.  

All the pieces of jewellery illustrated in this blog, will be sold in the Jewellery, Watches & Silver Sale on 13th January.


View Sale Details

Sarah Hardy

Sarah Hardy

LL.B. (Hons) PJ.Dip. FGA DGA

Jewellery Consultant

+ 44 (0) 1969 623780

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