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Quartz is one of the most common minerals on the British Isles. It is a component of many rock types and can be found as beautiful crystal clusters. In addition, it plays a very important role in the history and folklore of the British Isles.
Quartz and rock crystal, geology
Quartz is actually the name for a group of minerals, a large and important group. Many of the well-known minerals such as rock crystal, amethyst and agate belong to this group. The origin of the quartz name is unclear. It is probably from Saxon, but there are also references to an older Slavic origin. Quartz is also called crystal, after the Greek Kristallos, which means ice cold. The ancient Greeks thought that the colorless quartz was eternally frozen ice.
All quartz types are based on the chemical formula SiO2, silicon dioxide. The purest form of these are colourless crystals, which we call rock crystal lor rock quartz. Other members of the quartz group include amethyst, citrine, agate, jasper, and flint.
Quartz is the second most common mineral on earth. 12% Of the volume of the earth’s crust consists of quartz. It is the most important component of, for example, granite, but also sand. If you look at beach sand under the microscope you will mainly find quartz grains.
Quartz has Mohs hardness 7. So it is a relatively hard mineral, you can scratch a piece of glass with it. The crystal form of quartz is trigonal (sometimes hexagonal). All quartz crystals form a hexagon with a hexagonal pyramid on top. This is one of the easiest recognizable features to distinguish quartz from other minerals that may look like it.
On the basis of this crystal form, quartz is subdivided into two groups.
- Macrocrystalline quartz is quartz whose crystals we can see with the naked eye. This includes amethyst, rock crystal, smoky quartz and citrine, but also rose quartz. Although most rose quartz pieces you see have no crystals, rose quartz can indeed form beautiful crystals.
- Cryptocrystalline quartz is quartz whose individual quartz crystals are indistinguishable and can only be seen with a strong microscope. This includes agate, jasper, chalcedony, onyx and also flint.
Rock crystal is therefore the most pure, colorless form of quartz. It occurs almost everywhere in the world. It can form in cavities (geodes), crevasses, pebbles, caves, etc. The name rock crystal is a somewhat confusing name. Colourless quartz is often referred to simply as “quartz”. When is a quartz rock crystal and when is it quartz? According to mindat.org, the leading mineral website, rock crystal is a variety of quartz. The term quartz is usually used for rock-forming colourless quartz and quartz in fully filled veins in rock. The name rock crystal is often reserved for colourless quartz with crystal points on it, but this is not a hard dividing line. For clusters with crystals you will often see the designation quartz instead of rock crystal. Quartz is sold 9 out of 10 times from Brazil or Madagascar. But other places are also suppliers of beautiful rock crystals, for example Arkensas rock crystal is also very beautiful clear rock crystal. Rock crystal is very common and the trade is responding to it in a handy way. Rock crystal or quartz is nowadays marketed under numerous other fancy names, making it sometimes difficult to see the wood for the trees. Think of azeztulite (for that it must come from a certain area in America, unless it is called satya mani azeztulite, then it comes from India), lodolite (rock crystal with inclusions that form a small ‘landscape’ in the stone), golden healer (rock crystal with limonite or hematite discolouration), Maria Magdalena quartz (quartz with a pink / red color due to hematite), Tibetan quartz (you probably guess where it comes from) and many other names. Sometimes it is treated with titanium and gets all the colors of the rainbow, this is called aura quartz. The type of growth sometimes gives a name to the quartz. For example with elestial quartz, recordkeeper quartz, candle quartz, Lemurian seed quartz, skeleton quartz, floaters, cathedral quartz, laser quartz, faden quartz and fairy quartz. This list of names seems to grow every year.
Quartz in the history and folklore of the British Isles
Quartz and rock crystal are found in many places in Great Britain. Quartz as a rock-forming mineral can be found almost everywhere, from the coast of Cornwall to the Scottish highlands. Beautiful rock crystal clusters are found in Cornwall, in the mining area of St Austell and in Northern England. In Derbyshire you can find the “Buxton Diamonds”, a double terminated form of rock crystal that, in the past, was considered by the locals as diamonds and used for jewelry. The name of diamond for rock crystal is used often. We also know Cornish Diamonds from Cornwall, of course, and the well-known Herkimer diamonds from America which are actually rock crystals.
Quartz veins are a source of gold in some places, including the British Isles. Gold is often found in these quartz veins and therefor quartz was being mined for gold in some areas. In other places gold was found by ‘panning’ it from the river. Not only gold, but various other metals are found in combination with quartz.
Small quartz crystals can also be found in flint nodules in southern England, from Kent to Dorset. If you visit a beach there, it is often full of flint pebbles. Flint is also a type of quartz and in cavities in the flint you can sometimes find small sparkling crystals. These are quartz crystals. Sometimes you find spherical or botryoidal crystals in flint, these are chalcedony crystals, chalcedony os also a type of quartz.
Because quartz was so easily available and naturally very beautiful, it played a very important role in the lives and beliefs of the people on the British Isles in the past.
In addition to being used as a tool or weapon, another use of quartz is widely spread throughout the British Isles. In many cases white quartz pebbles are found in graves. Sometimes spread over the entire grave, sometimes in front of the entrance, grouped together as a pillow for the deceased, in the hand or even in the mouth (Lebour 1914). Quartz is also a widely used material such as the construction or decorative stone of tombs. The best-known example in natural can be found in Ireland, Newgrange, where quartz is used to coat the tomb on the outside which makes for a special sight when the sun shines on this white quartz stone and the hill is bathed in a sea of white shining light. This must have been important at the time, because the stone used for this is not a local stone. The large chunks were removed from at least 50 kilometers away (Thompsom 2006). The Irish also have a name for quartz stones, they are called clocha geala, which means radiant stones or clocha bána, white stones. Later names like Godstones or Marystones were also used.
Quartz stones are the stones of the sí, the fairy people in Ireland. The word sí is also sometimes the word for hill or burial mound where the fairy people live. According to the legends, quartz stones were not stones for the living.
Quartz boulders were used to build burial mounds, sometimes in combination with local granite. Examples of this can be found in Connemara. Some stone circles, including those from Men an Tol in Cornwall, often have 1 or 2 quartz stones in addition to the local stones. This was probably the entrance to the circle. Also at the Clava Cairns, a Bronze Age burial mound complex in Scotland, the types of stones were deliberately chosen.
Here, probably with an intention, quartz stone is used and 1 stone of a striking pink granite type. Many small quartz stones were found in and around the burial mounds at the Clava Cairns, and research has shown that these quartz stones were already scattered around the site before the large stones were placed. Not in a natural way, because they are all stones rounded off by the river that must have been brought there and they also lie only on that part (Bradley 1996). When in Inveraray, Scotland, 8 Bronze Age graves were discovered that were adorned with groups of white quartz pebbles, the locals knew how to lay white quartz stones on the grave of a friend or loved one in that area was a custom for a long time. Groups of quartz stones in tombs have also been found in Kilmartin Glen in Scotland, part of which can now be viewed in the museum in Kilmartin. Not only in Scotland, but also in England, countless Stone Age and Bronze Age graves containing white quartz stones have been found. Quartz stones were also found in urns with cremation remains.
This belief continued until the Middle Ages. Various shrines in which relics of the dead were preserved, including a number of St Patrick shrines, were covered with quartz.
Various explanations have been suggested about this age-old use of quartz, including the suggestion that it was seen as a stone that was an energy source that gave the dead the power to travel to the other world, the realm of the dead (Darvill 2002). But giving an explanation for this use of course is speculating.
Special are the finds of quartz stones on the Shetland islands on which patterns are drawn. Part of these drawn stones were found in settlements that are attributed to the Picts. The function of these quartz stones with line patterns and dots is unclear. Explanations range from weapons, sling stones, where the patterns were unique per person and the stones could later be found by the owner (Hamilton, 1968), to ritual stones by Pictian shamans (Ritchie 1998). The mystery is how these people were able to paint the stones. A painted stone has been found on Orkney that appears to have been treated with hematite, which occurs locally there. Microscopic examination of the stones of Shetland says that the drawings have been processed with burnt organic material. Experiments with that peat was burned and the tar-like substance obtained from it appear to be colours and the same type of discolouration then caused the historic stones (Arthur 2014).
Quartz, according to tradition in Scotland, England and Ireland, also had a medicinal effect. This is known in many places in the world for quartz. Until the Middle Ages, quartz and quartz powder were considered medicinal in various European countries. Even Mary, Queen of Scots, was a great lover of healing stones.
In various places in both Ireland and Scotland, why on Iona, large stones with round recesses would have been located. There were white quartz pebbles in these recesses that had to ensure healing. In most cases it was nine stones, nine is a sacred number for the pre-Christian and early Christian population in Ireland and Scotland. Columba itself is said to have used white stones from the water for healing. Stories from ancient Ireland tell of white quartz stones that have to be boiled in water with sage to make the water medicinal. Another story is of an old witch in Sutherland who threw quartz stones into Lochmonar and everyone who subsequently bathed in the loch was healed of all kinds of ailments.
All in all, quartz is a stone with a fascinating history that continues to this day. Quartz has a proven property that is particularly valuable for science. It is piezoelectric and therefore produces a small electrical voltage when it comes under pressure. This energy can be converted into a pulse, a vibration. Quartz has a very stable, demonstrable vibration frequency and can stabilize and amplify existing vibration frequencies. We call this phenomenon osscilation. That is why quartz is a very useful material in, for example, timepieces (the well-known “quartz” timepieces and watches) and in communication equipment. In the Second World War in particular, the demand for quartz increased enormously and huge quantities of quartz crystals were taken from Brazil and exported to America. Quartz was a particularly valuable product at the time. To date, quartz has countless industrial applications, but now it is mostly quartz that has grown in a laboratory that is used. Natural quartz is rarely used in industry anymore.