Feldspar: Varieties of the Most Common Mineral on Earth

The feldspar group includes the following minerals: albite, andesine, anorthoclase, bytownite, labradorite, oligoclase, orthoclase, microcline, sanidine. Varieties: amazonite, aventurine feldspar (sunstone), microcline-perthite, moonstone, adularia.

The history of the origin of the name was specially studied by Zenzen and Spencer. The term was first introduced by Tilas in 1740 - feldtspat, from Swedish, feldt or fait (field, arable land) and German spath (plate, bar). In “Mineralogy” Vallerius proposed another term - feltspat, from Swedish, felt (moraine field, glacial valley) and spat (tablet, knockouts along the cleavage). In the German translation of Wallerius's Mineralogy (1750), the term is modified as feldspath (“feldspar”), and in English (1772) as fieldspar. As a result of their confusion, the modern term appeared - feldspar. In addition, in the 2nd edition of Kirwan’s Mineralogy (1794), the term felspa is used, from the German fels (rock, rock), i.e. “rock-forming” spar.

Less commonly used terms: felspar (English), feldspath (French).

Feldspar

Properties

The feldspar group minerals are a large and diverse family.

The composition of minerals is complex and varied.

This is a group of aluminosilicates.

General properties:

• hardness 6 on the Mohs scale;
• cleavage perfect in two directions;
• monoclinic or triclinic system (barium banalsite and strontium stronalsite have rhombic system);
• dash color is white;
• density 2.55-2.76 (for barium feldspars up to 3.4);
• The mineral has a wide range of colors: from white, through brown of varying saturation, to bluish.

All feldspars react with hydrofluoric acid; Hydrochloric acid is also destructive for plagioclases.

Among the feldspars, the following varieties are distinguished:

1. Plagioclases (formula NaAlSi3O8-CaAl2Si2O8). Conventionally divided into 6 mineral types. Examples: albite, labradorite, oligoclase, andesite.
2. Potassium-barium feldspars (KAlSi3O8-BaAl2i28). Hyalophane, celsian.
3. Potassium feldspar (KAlSi3O8). Microcline, orthoclase, adularia, sanidine.
4. Calica feldspar (K,Na) AlSi3O8. Sanidine, anorthoclase.

Intergrowths of quartz with microcline are called Jewish stone or written granite.

Formula	{ K, Na, Ca, sometimes Ba }{ Al2Si2 or AlSi3 }O8
Color	White to bluish or reddish
Stroke color	white
Shine	Glass
Transparency	Translucent to transparent
Hardness	5—6,5
Cleavage	Perfect
Density	2.54—2.75 g/cm³
singonia	Monoclinic or Triclinic
Refractive index	1,554—1,662

We recommend: KYANITE - a mineral abused by nature

Some of the spars look very attractive. They are used as ornamental stones.

Cut options

Feldspar specimens are best paired with cabochon cuts. This type of processing allows you to emphasize the natural beauty of the mineral, making the effects of iridescence, shillerization, etc. even more noticeable. Colorless specimens can be subjected to other cutting options.

What metals are they combined with?

The minerals are quite hard and durable, which is why they are popular in the jewelry world. From different types of spar, both simple and inexpensive jewelry and exclusive products and sets are created. Silver and white gold are more often used as frames for rocks with iridescence or pronounced cold shades, and less often medical alloy and cupronickel. Warm-colored stones pair perfectly with red and classic yellow gold.

Imitations of spar - what are they?

More often, glass with copper particles is used as an imitation of, for example, heliolite. Belomorite or adularia is counterfeited using frosted light-scattering glass.

Production

The origin of feldspars is mainly volcanic and igneous.

Minerals are mined all over the world (except for the Arctic and Antarctic).

Deposits of the most common group of minerals are:

• USA;
• Sweden;
• Madagascar;
• India;
• Ukraine.

Russia is rich in such minerals:

• Transbaikalia;
• Chelyabinsk region;
• Sverdlovsk region;
• Tyva;
• Chukotka.

Potassium feldspars are mined mainly from pegmatite ores. Along the way, columbite, mica, and beryl are mined.

Potassium feldspars

History and origin of the stone

Translated from German “spar” means “bar”. When the fields were plowed, they found minerals in the shape of a rectangle, which gave the name to the stone. Feldspar has been known to mankind for many hundreds of years:

• in Ancient Egypt, figurines were made from it;
• in Mesopotamia it served as a material for decoration;
• used for making household items and household utensils;
• in China it was mixed with clay to create porcelain.

Feldspar is formed under the influence of high temperature in an acidic environment. Igneous rock first forms plagioclase, which can transform into the more acidic potassium spar.

Application

Such a rich and accessible material as feldspars has found application in many industries.

• Potassium feldspars are used in the production of electrical ceramics. Porcelain teeth and opalescent glass are made from this variety.
• Labradorite is used for the production of facing tiles.
• Fluxes made from feldspar minerals are used in welding and metallurgy.
• Many feldspars have a slight abrasive effect when crushed. It is used in the production of toothpaste and cleaning products.
• Jewelry made from adularia, amazonite, and sunstone are inexpensive and beautiful jewelry.
• Many glazes and enamels require plagioclases.
• Potassium-barium feldspars are rare. Interesting specimens have value for collectors and mineral enthusiasts.
• The trace element rubidium is incidentally mined during the development of amazonite deposits.

How to spot a fake

Minerals such as feldspar are also counterfeited. For example, the most expensive adularia is considered to be a gem mined in Sri Lanka. Cheap imitation of such stones are glass or plastic.

It is not difficult to distinguish a natural moonstone from a fake:

• Look at the light through the stone - a real adularia will shimmer inside and play with colors. This effect cannot be faked.
• Glass or plastic will quickly heat up in the palms, natural stone will not.
• Natural adularia is smooth to the touch, soft like silk fabric.

It is almost impossible to counterfeit Labradorite due to the special play of colors - labradorization. This mineral shimmers with a full rainbow spectrum, creating the effect of a three-dimensional northern lights.

Amazonite is not so expensive that it can be counterfeited. But if you still have to doubt, then a proven method of determining thermal conductivity will come to the rescue - a natural mineral is always cool. In addition, a distinctive feature of Amazonite is its internal structure, due to which the surface of the stone is endowed with a pattern in the form of a grid of squares.

Lithotherapists advise

Products made from some varieties of the mineral (according to lithotherapists) have healing properties.

Amazonite is used for massages (anti-cellulite and general). The stone will help with osteochondrosis and arthritis, normalizes metabolic processes. Wear Amazonite jewelry regularly if you have dermatitis or eczema.

Amazonite

In the old days, it was believed that jewelry with amazonite healed the heart, thyroid gland, and lungs.

Labradorite (according to lithotherapists) will alleviate colds, strengthen the immune system, and help cure diseases of the genitourinary system.

Labrador

Important for many: lithotherapists believe that the mineral normalizes blood pressure and heals blood vessels. We recommend: OBSIDIAN - devil's claw, Apache tears

Sun stone (heliolite) is recommended for older people. It is recommended to wear jewelry at all times. Lithotherapists believe that the stone gives vigor and increases vitality. The stone has a tonic effect.

Heliolite

adularia in the East has been a stone that continues the family line. More precisely, he helped women get pregnant. After all, the main thing (from the point of view of an Eastern person) is to leave its continuation on earth. A moonstone amulet protects travelers.

Adularia

But the stone is not simple. He does not like duplicity, lies, deceit. Give jewelry with adularia to harsh, tough, cold people. The mineral will help awaken the warmth of the soul and compassion for others in the owner of the jewelry.

Mineral composition

Almost all varieties of the mineral are similar in physical properties with the same chemical composition. Representatives of this rock are presented in the form of twin crystals, are distinguished by the presence of mother-of-pearl or glass luster, have an average level of hardness, perfect cleavage and have a distinct iridescent effect.

Man has been mining minerals for many hundreds of years and actively using them in everyday life and industry. From German the name of this group of minerals is translated as “splitting into plates.” The name in this case fully describes the structure and appearance of the rock.

The magic of feldspars

Some varieties of the mineral have magical properties (according to esotericists and fans of the occult).

Particular attention is paid to moonstone (adularia). Labrador is not left out. Both stones are excellent protectors of the owner from negative influences, from troubles and the evil eye.

Adularia, as esotericists say, is directly related to the phases of the night star. From the new moon onwards, the magical properties of the stone increase, reaching their maximum during the full moon.

Adulari

The difference is that Adularia is more suitable for young people, while the energy of Labrador Retriever opens up more fully with older owners.

Labradors are also associated with the Moon, but they are Dark Moon stones. Necromancers, witches and sorcerers need a stone. It (according to esotericists) facilitates communication with the other world.

Amazonite is the keeper of the hearth and the protector of the marital union. For the stone to work, you need paired jewelry with the gem for the spouses.

Amazonite

Labradorite has the same properties.

Minerals relieve depression and put the owner of jewelry with a gem in a positive mood.

Important: do not let anyone try on jewelry with a Labrador. The gem is able to appropriate any energy. And it’s not a fact that it will turn out to be good.

The sun stone is recommended for travelers and anyone who loves active recreation. The gem does not like homebodies and will encourage the owner to travel, active recreation and even adventures.

We recommend: Decorative Crimson Quartzite

But for those who are interested in the occult, jewelry with a sun stone is not recommended. The owner of such jewelry can easily get into some sect, non-traditional religious organization.

How to wear

All jewelry feldspars used in jewelry are completely different. However, the colors that nature has endowed them with are universal and suitable for almost any wardrobe and type of appearance.

The best option is the contrast of the image. Therefore, items with Labradorite are not worn with black clothes, and moonstone will not look good with white ones.

Evening dresses are well complemented by massive jewelry. During the day, neat, discreet accessories are more appropriate, especially for office style. Amazonite is not an evening stone.

Amazonite bracelet

Important! Moonstone is worn during the waxing moon phase. Then the mineral is fully revealed. When the Moon wanes, the adularia is fueled by the energy of the owner. Therefore, during this period it is better to hide the decoration away.

Adularia will look great on blue-eyed blondes. Amazonite will highlight those with green eyes. Labradorite is appropriate on mature women - this applies to both the appearance and the energy of the stone.

The stars speak

According to the zodiac sign, Amazonites will bring great benefits to Libra, Capricorn, Virgo, and Pisces.

Adularia is a gem for Cancers and Pisces. But these zodiac signs are not recommended to wear jewelry with adularia on the waning Moon. Esotericists say that at this time the moonstone needs energy. And he will pull it wherever possible. And the closest one is usually the owner...

The gem is contraindicated for fire signs.

The sun stone will gladly help any zodiac sign to heal. The magical properties of heliolite are most suitable for the Fire signs: Leo, Aries, Sagittarius.

The stone is least suitable for Water signs, but it will not cause harm - it will be a simple decoration.

Labradors have a weakness for Water signs. Therefore, Pisces, Cancers, Scorpios will receive any help that the stones can provide.

The stone is indifferent to other signs of the Zodiac.

How to care

Feldspars need careful care. It doesn’t matter whether it’s Labradorite, Amazonite or Adularia. Recommendations for caring for spar:

• These minerals cannot withstand physical stress, so mechanical cleaning is prohibited for them. Ultrasound and the use of any chemicals are also unacceptable. It is enough to wash the products under running water or a weak soap solution, wiping them with a soft cloth afterwards.
• Store separately from other jewelry, wrapped in a soft cloth.
• Before doing housework, going to the gym or going to the beach, you should take off your jewelry. Amazonite is especially sensitive to sunlight - the stone loses color irrevocably.

Labradorite, like adularia, is closely associated with the moon. Therefore, these minerals require periodic recharging with moonlight.