America
Tumbled Stone Collection
Come with us and discover the amazing mineral wealth hidden in the vast American continent. Our collection of tumbled stones will introduce you to rare gems from different parts of the Americas, from majestic mountains to deep rainforests.


ROCK CRYSTAL (Brazil)
- 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.

AMETHYST (Brazil)
- 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.

SMOKY QUARTZ (Brazil)
- 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.

GARNET (Brazil)
- Characteristics: Garnet represents a whole group of minerals with colors that can be very diverse. The individual types primarily differ in their chemical composition. The presence of specific elements creates a wide spectrum of colors that blend into one another. For example, we distinguish between red almandine, orange spessartine, and green uvarovite, among other varieties. Due to its hardness, garnet is also found in alluvium and is mined for use in jewelry, such as the Czech pyrope.
- Formation: Garnet crystallizes during the metamorphism of rocks under high pressure and temperature. It forms especially during the transformation of clay-rich rocks into gneiss and schist. This mineral often appears as well-developed dodecahedral crystals.
- Occurrence: Garnets are found primarily in metamorphic rocks and pegmatites worldwide. Significant deposits are located in India, Tanzania, China, and Brazil. Our stone comes from the Rodolita mine in the state of Tocantins, Brazil.

ROSE QUARTZ (Brazil)
- 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 particular stone comes from the state of Minas Gerais in Brazil.

VOLCANIC BRECCIA (Peru)
- Characteristics: Volcanic breccia is a rock composed of fragments of volcanic rocks cemented together. It can contain a variety of colors and structures, which often gives it a "wild" look. Due to its unique appearance, it is popular for making jewelry and decorations.
- Formation: The stone is formed during explosive volcanic activity - eruptions tear the rocks apart, which then mix with ash and lava. Under the influence of pressure and heat, this mixture gradually solidifies into a solid rock.
- Occurrence: Volcanic breccias are associated with volcanic activity zones. Our stone comes from Peru.

YELLOW CALCITE (Mexico)
- Characteristics: Calcite, also known as calcium carbonate, occurs in many color variations depending on its admixtures. The yellow-orange color, which is highly prized in calcite, is caused by the presence of manganese and iron. It is a very brittle and cleavable stone, and for this reason, it is processed only by hand.
- Formation: It is formed hydrothermally in solutions rich in CaCO3 (calcite), which settles along with elements such as iron and manganese.
- Occurrence: Deposits of carbonate rocks in northern Mexico are the source of massive veins of yellow calcite, which is industrially mined. During mining, it is sorted by quality suitable for processing. This particular stone was crafted from the highest-quality raw material

BLUE AVENTURINE (Brazil)
- 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.

HEMATITE (Brazil)
- Characteristics: Hematite, also known as ferric oxide, is quite widespread in nature. The highest quality stones are also suitable for use in jewellery making. Because of its metallic luster, it's used to produce cabochons and decorative objects. Bracelets and necklaces made from these stones are also very popular, but synthetic stones are generally used for their production.
- Formation: Hematite forms primarily in metamorphosed (transformed) banded iron formations. These are layered rocks rich in iron and quartz.
- Occurrence: Significant deposits are located in Brazil in the state of Minas Gerais. Material with a high iron content (up to 65%) is mined there and is suitable for use in jewellery. Our stone also comes from this region.

