Concept

Onyx

Related concepts (11)
Engraved gem
An engraved gem, frequently referred to as an intaglio, is a small and usually semi-precious gemstone that has been carved, in the Western tradition normally with images or inscriptions only on one face. The engraving of gemstones was a major luxury art form in the Ancient world, and an important one in some later periods. Strictly speaking, engraving means carving in intaglio (with the design cut into the flat background of the stone), but relief carvings (with the design projecting out of the background as in nearly all cameos) are also covered by the term.
Chalcedony
Chalcedony (kælˈsɛdəni , or ˈkælsəˌdoʊni ) is a cryptocrystalline form of silica, composed of very fine intergrowths of quartz and moganite. These are both silica minerals, but they differ in that quartz has a trigonal crystal structure, while moganite is monoclinic. Chalcedony's standard chemical structure (based on the chemical structure of quartz) is SiO2 (silicon dioxide). Chalcedony has a waxy luster, and may be semitransparent or translucent.
Hardstone carving
Hardstone carving, in art history and archaeology, is the artistic carving of semi-precious stones (and sometimes gemstones), such as jade, rock crystal (clear quartz), agate, onyx, jasper, serpentinite, or carnelian, and for objects made in this way. Normally the objects are small, and the category overlaps with both jewellery and sculpture. Hardstone carving is sometimes referred to by the Italian term pietre dure; however, pietra dura (with an "a") is the common term used for stone inlay work, which causes some confusion.
Brooch
A brooch (ˈbroʊtʃ, also USˈbruːtʃ) is a decorative jewelry item designed to be attached to garments, often to fasten them together. It is usually made of metal, often silver or gold or some other material. Brooches are frequently decorated with enamel or with gemstones and may be solely for ornament or serve a practical function as a clothes fastener. The earliest known brooches are from the Bronze Age. As fashions in brooches changed rather quickly, they are important chronological indicators.
Seal (emblem)
A seal is a device for making an impression in wax, clay, paper, or some other medium, including an embossment on paper, and is also the impression thus made. The original purpose was to authenticate a document, or to prevent interference with a package or envelope by applying a seal which had to be broken to open the container (hence the modern English verb "to seal", which implies secure closing without an actual wax seal). The seal-making device is also referred to as the seal matrix or die; the imprint it creates as the seal impression (or, more rarely, the sealing).
Agate
Agate (ˈæɡɪt) is the banded variety of chalcedony, which comes in a wide variety of colors. Agates are primarily formed within volcanic and metamorphic rocks. The ornamental use of agate was common in Ancient Greece, in assorted jewelry and in the seal stones of Greek warriors, while bead necklaces with pierced and polished agate date back to the 3rd millennium BCE in the Indus Valley civilisation.
Cameo (carving)
Cameo (ˈkæmioʊ) is a method of carving an object such as an engraved gem, item of jewellery or vessel. It nearly always features a raised (positive) relief image; contrast with intaglio, which has a negative image. Originally, and still in discussing historical work, cameo only referred to works where the relief image was of a contrasting colour to the background; this was achieved by carefully carving a piece of material with a flat plane where two contrasting colours met, removing all the first colour except for the image to leave a contrasting background.
Jewellery
Jewellery (or jewelry in AmE) consists of decorative items worn for personal adornment, such as brooches, rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the clothes. From a western perspective, the term is restricted to durable ornaments, excluding flowers for example. For many centuries metal such as gold often combined with gemstones, has been the normal material for jewellery, but other materials such as glass, shells and other plant materials may be used.
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at .
Carnelian
Carnelian (also spelled cornelian) is a brownish-red mineral commonly used as a semiprecious stone. Similar to carnelian is sard, which is generally harder and darker; the difference is not rigidly defined, and the two names are often used interchangeably. Both carnelian and sard are varieties of the silica mineral chalcedony colored by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration. Significant localities include Yanacodo (Peru); Ratnapura (Sri Lanka); and Thailand.

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