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ROCK CRYSTAL

• Characteristics: Rock crystal is a transparent and clear variety of quartz, representing one of the purest forms of silicon dioxide. It is distinguished by its glassy luster, high hardness (grade 7 on the Mohs scale), and exceptional durability. Due to its piezoelectric properties, it has a wide range of uses in many industrial fields and in jewelry making.
• Formation: It is formed by the long-term crystallization of silica from hot aqueous solutions inside rock cavities, often in so-called hydrothermal veins. The crystals can grow for millions of years.
• Occurrence: Significant deposits are found in Brazil, the Alps (especially Switzerland), and the United States. In the Czech Republic, it is found, for example, in Moravia, specifically in the Vysočina region. Rare large crystals come from Madagascar. This particular stone comes from the state of Minas Gerais in Brazil.

ROSE QUARTZ

• Characteristics: Rose quartz is a light to deep pink variety of quartz, which is often milky and cloudy. While it was previously thought that its color was due to the presence of manganese, more recent scientific studies have shown that the color is actually caused by fine inclusions of the mineral dumortierite. Rose quartz is very popular in jewelry and as a decorative stone.
• Formation: It forms in the inner parts of pegmatite veins, where it slowly crystallizes from mineral solutions. The pink color of the stone can gradually fade due to sunlight.
• Occurrence: Most rose quartz is mined in Brazil and Madagascar, but it also occurs in the USA, India, and the Czech Republic (for example, in the Vysočina region). This stone comes from mines on the border between Namibia and South Africa.

AMETHYST

• Characteristics: Amethyst is a purple-colored variety of quartz. It owes its color to its iron content and the effects of natural radioactivity. It is a prized gemstone that was popular even in ancient times. Its shades range from a delicate light purple to a rich dark shade.
• Formation: Amethyst crystallizes from hot solutions that penetrate into rock cavities, especially in volcanic environments. It often forms crystals on the walls of the cavities - the so-called amethyst geodes.
• Occurrence: The most important deposits are found in Brazil (the Rio Grande region), as well as Uruguay, Russia (the Urals), Slovakia (Štiavnica), and the Czech Republic (Krušné hory). Our stone comes from mines near the city of Marabá in the Brazilian state of Pará.

CITRINE

• Characteristics: Citrine is an attractive version of quartz, but the raw material is very rare in nature. Citrine is therefore often produced by heat-treating amethyst – the transformation of bivalent iron into trivalent iron causes the purple color to change to yellow. Citrines processed from high-quality Brazilian amethyst excel with a beautiful golden-yellow hue and substitute for the often unaffordable natural citrines.
• Formation: Citrine forms naturally in pegmatites or hydrothermal veins. Its color is due to trace amounts of Fe³⁺ in the crystal lattice. However, most citrines on the market are treated by heat or radiation.
• Occurrence: Citrine occurs mainly in pegmatites, for example, in Brazil, Russia, and Madagascar. Our stone is from Brazil and has been heat-treated.

AMETHYST CHEVRON

• Characteristics: Chevron amethyst is an attractive variety of amethyst characterized by distinctive V-shaped banding. It combines the purple color of amethyst with white to gray layers of quartz. It has a glassy luster and is semi-translucent to transparent.
• Formation: This stone forms from the deposition of silica-rich solutions in rock cavities. During this process, layers rich in silicon oxide with iron impurities (amethyst) alternate with purer layers of milky quartz. Natural radiation then causes the iron-containing layers to transform into amethyst and gain their typical purple color. The regular alternation of these layers creates the characteristic chevron-shaped bands.
• Occurrence: Significant deposits of Chevron Amethyst are located in Brazil and Zambia, which produce the highest-quality pieces. Other locations include Namibia, India, the USA, and Russia. This particular stone comes from Zambia.

AVENTURINE

• Characteristics: Aventurine is a shimmering variety of fine-grained quartz that occurs in various colors, from red, yellow, and blue to green and brown. Most often, aventurine boasts a beautiful green hue, which is caused by a mixture of fine scales of chromian mica (fuchsite). The stone is characterized by a typical shiny appearance, known as aventurescence.
• Formation: The stone is formed in metamorphic and pegmatite rocks, where tiny mineral particles penetrate into the quartz. It is these inclusions that give aventurine its specific color and sparkle.
• Occurrence: High-quality aventurine is mainly mined in India, Russia, Brazil, and China. This stone comes from Zimbabwe.

BLUE AVENTURINE

• Characteristics: Blue quartz, sometimes called blue aventurine, is a very interesting colored variety of cryptocrystalline quartz. It owes its blue colour to the fine crystals of the mineral dumortierite dispersed in the quartz mass. Depending on the intensity of the dumortierite inclusions, the colour of the quartz changes from light to deep blue.
• Formation: The formation of blue aventurine is a long-term process that takes place deep beneath the Earth's surface. During the slow cooling of magma rich in silica compounds, quartz crystallizes. If there's a high concentration of iron and aluminum in the surrounding area, inclusions of the mineral dumortierite can form within the crystalline mass of the quartz, causing the otherwise grayish-white quartz to turn blue.
• Occurrence: The main deposits of blue aventurine are located in the state of Minas Gerais, Brazil. This stone also comes from there.

ROCK CRYSTAL WITH RUTILE

• Characteristics: Rock crystal with rutile inclusions is a highly sought-after stone among both collectors and jewelers. The golden crystals of rutile, sometimes called Venus hair, can create beautiful starburst patterns with a hematite center within the quartz. If the quartz is clear, the price of such stones can reach astronomical sums.
• Formation: The crystallization of quartz in natural conditions is a long-term geological process that takes millions of years. During this time, changes in pressure, temperature, or the chemical composition of the environment can interrupt the growth of crystals and release other minerals from surrounding rocks. At that moment, the quartz can trap and enclose fragments of other minerals, such as rutile.
• Occurrence: The main deposits of rutilated quartz are in Namibia, Zambia, and Madagascar, but the most beautiful stones are found in Brazil. This stone also comes from the state of Minas Gerais in Brazil.

SMOKY QUARTZ

• Characteristics: Smoky quartz is a smoky-brown to black variety of quartz. Its coloration is caused by aluminum ions (Al³⁺) within the crystal lattice, which change color after being exposed to natural radiation. The intensity of the color depends on the amount of these ions in the crystal lattice. When heated, the stone can lighten or even transform into citrine.
• Formation: The stone forms during the crystallization of quartz in pegmatites, Alpine veins, and metamorphic rocks. The brown color of the originally clear rock crystal is caused by natural radioactive radiation from surrounding minerals that act on the aluminum atoms present in the lattice.
• Occurrence: The main deposits of smoky quartz are located in Brazil, the Alps, and the Urals, as well as in the Czech Republic. A large amount of the smoky quartz from Brazil on the commercial market is actually artificially irradiated rock crystal. Our stone comes from Minas Gerais, Brazil, and has not been artificially irradiated.