Garnet in the context of Porphyroblast

A necklace is an article of jewellery that is worn around the neck. Necklaces may have been one of the earliest types of adornment worn by humans. They often serve ceremonial, religious, magical, or funerary purposes and are also used as symbols of wealth and status, given that they are commonly made of precious metals and stones.

The main component of a necklace is the band, chain, or cord that wraps around the neck. These are most often rendered in precious metals such as gold, silver, and platinum. Necklaces often have additional attachments suspended or inset into the necklace itself. These attachments typically include pendants, lockets, amulets, crosses, and precious and semiprecious materials such as diamond, pearls, rubies, emeralds, garnets, and sapphires. They are made with many different type of materials and are used for many things and sometimes classified as clothing.

The upper mantle of Earth is a very thick layer of rock inside the planet, which begins just beneath the crust (at about 10 km (6.2 mi) under the oceans, and about 35 km (22 mi) under the continents) and ends at the top of the lower mantle, at about 670 km (420 mi). Temperatures range from around 900 K (627 °C; 1,160 °F) at the upper boundary with the crust to around 1,200 K (930 °C; 1,700 °F) at the boundary with the lower mantle. Upper mantle material that has come up onto the surface comprises about 55% olivine, 35% pyroxene, and 5–10% of calcium oxide and aluminum oxide minerals such as plagioclase, spinel, or garnet, depending on depth.

A silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula [SiO
_4−x]
_n, where 0 ≤ x < 2. The family includes orthosilicate SiO4−4 (x = 0), metasilicate SiO2−3 (x = 1), and pyrosilicate Si₂O6−7 (x = 0.5, n = 2). The name is also used for any salt of such anions, such as sodium metasilicate; or any ester containing the corresponding chemical group, such as tetramethyl orthosilicate. The name "silicate" is sometimes extended to any anions containing silicon, even if they do not fit the general formula or contain other atoms besides oxygen; such as hexafluorosilicate [SiF₆]. Most commonly, silicates are encountered as silicate minerals.

For diverse manufacturing, technological, and artistic needs, silicates are versatile materials, both natural (such as granite, gravel, and garnet) and artificial (such as Portland cement, ceramics, glass, and waterglass).

Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of 150 °C (300 °F), and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface.

Various forms of metamorphism exist, including regional, contact, hydrothermal, shock, and dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as prograde metamorphism, while decreasing temperature and pressure characterize retrograde metamorphism.

The Ruby Mountains (Shoshoni: 'Duka Doya', meaning “Snowcapped”) are a mountain range, primarily located within Elko County with a small extension into White Pine County, in Nevada, United States. Most of the range is included within the Humboldt-Toiyabe National Forest. The range reaches a maximum elevation of 11,387 feet (3,471 m) on the summit of Ruby Dome. To the north is Secret Pass and the East Humboldt Range, and from there the Rubies run south-southwest for about 80 miles (130 km). To the east lies Ruby Valley, and to the west lie Huntington and Lamoille Valleys. The Ruby Mountains are the only range of an introduced bird, the Himalayan snowcock, in North America. The mountain range was named after the garnets found by early explorers. The central core of the range shows extensive evidence of glaciation during recent ice ages, including U-shaped canyons, moraines, hanging valleys, and steeply carved granite mountains, cliffs, and cirques.

Jewellery chains, jewelry chains or body chains are metal chains that are used in jewellery to encircle parts of the body, namely the neck, wrists and ankles, and they also serve as points to hang decorative charms and pendants.

In geometry, the rhombic dodecahedron is a convex polyhedron with 12 congruent rhombic faces. It has 24 edges, and 14 vertices of 2 types. As a Catalan solid, it is the dual polyhedron of the cuboctahedron. As a parallelohedron, the rhombic dodecahedron can be used to tesselate its copies in space creating a rhombic dodecahedral honeycomb. There are some variations of the rhombic dodecahedron, one of which is the Bilinski dodecahedron. There are some stellations of the rhombic dodecahedron, one of which is the Escher's solid. The rhombic dodecahedron may also appear in nature (such as in the garnet crystal), the architectural philosophies, practical usages, and toys.

Sand mining is the extraction of sand, mainly through an open pit (or sand pit) but sometimes mined from beaches and inland dunes or dredged from ocean and river beds. Sand is often used in manufacturing, for example as an abrasive or in concrete. It is also used on icy and snowy roads usually mixed with salt, to lower the melting point temperature, on the road surface. Sand can replace eroded coastline. Some uses require higher purity than others; for example sand used in concrete must be free of seashell fragments.

Sand mining presents opportunities to extract rutile, ilmenite, and zircon, which contain the industrially useful elements titanium and zirconium. Besides these minerals, beach sand may also contain garnet, leucoxene, sillimanite, and monazite.

The Staffordshire Hoard is the largest hoard of Anglo-Saxon gold and silver metalwork yet found. It consists of almost 4,600 items and metal fragments, amounting to a total of 5.1 kg (11 lb) of gold, 1.4 kg (3 lb) of silver and some 3,500 pieces of garnet cloisonné jewellery.It is described by the historian Cat Jarman as "possibly the finest collection of early medieval artefacts ever discovered".

The hoard was most likely deposited between 650 and 675 CE, and contains artefacts probably manufactured during the 6th and 7th centuries. It was discovered in 2009 in a field near the village of Hammerwich, near Lichfield, in Staffordshire, England. The location was in the Anglo-Saxon kingdom of Mercia at the time of the hoard's deposition.

Mining in Afghanistan is controlled by the Ministry of Mines and Petroleum in Kabul, which has offices in different parts of the country. Afghanistan has over 1,400 mineral fields, containing barite, chromite, coal, copper, gold, iron ore, lead, natural gas, petroleum, precious and semi-precious stones, salt, sulfur, lithium, talc, and zinc, among many other minerals. Gemstones include high-quality emeralds, lapis lazuli, red garnet and ruby. According to a joint study by The Pentagon and the United States Geological Survey, Afghanistan has an estimated US$1 trillion of untapped minerals.

There are six lapis mines in Afghanistan, the largest being located in Badakhshan province. There are around 12 copper mines in the country, including the Aynak copper deposit located in Logar province. Afghanistan's significance from an energy standpoint stems from its geographical position as a transit route for oil, natural gas, and electricity exports from Central Asia to South Asia and the Arabian Sea. This potential includes the construction of the Trans-Afghanistan Pipeline gas pipeline. The first Afghan oil production began in late 2012.

Chromitite is an igneous cumulate rock composed mostly of the mineral chromite. It is found in layered intrusions such as the Bushveld Igneous Complex in South Africa, the Stillwater igneous complex in Montana and the Ring of Fire discovery in Ontario.

Chromitite typically forms as orthocumulate layered lenses in peridotite rocks, at times intergrown with other oxides such as magnetite and ilmenite, and silicates such as olivine, pyroxene, plagioclase feldspar (mainly anorthite), and garnet crystals. The chromium rich garnet uvarovite forms in interbedded layers with chromitite.

A metamorphic reaction is a chemical reaction that takes place during the geological process of metamorphism wherein one assemblage of minerals is transformed into a second assemblage which is stable under the new temperature/pressure conditions resulting in the final stable state of the observed metamorphic rock.

Examples include the production of talc under varied metamorphic conditions:

The mineral pyrope is a member of the garnet group. Pyrope is the only member of the garnet family to always display red colouration in natural samples, and it is from this characteristic that it gets its name: from the Greek words for fire and eye. Despite being less common than most garnets, it is a widely used gemstone with numerous alternative names, some of which are misnomers. Chrome pyrope, and Bohemian garnet are two alternative names, the usage of the latter being discouraged by the Gemological Institute of America. Misnomers include Colorado ruby, Arizona ruby, California ruby, Rocky Mountain ruby, Elie Ruby, Bohemian carbuncle, and Cape ruby.