| Formula |
|Silica (silicon dioxide, SiO2)|
|Formula mass||60 g/mol|
|Color||Red, orange, reddish|
|Fracture||Uneven, splintery, conchoidal|
|Mohs scale hardness||6.5 – 7.0|
|Luster||Waxy to resinous|
|Diaphaneity||Translucent to opaque|
|Specific gravity||2.58 - 2.64|
|Optical properties||Uniaxial +|
|Refractive index||1.535 to 1.539|
|Birefringence||0.003 to 0.009|
Carnelian (also spelled cornelian  ) is a brownish-red mineral commonly used as a semi-precious gemstone. 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.  It has been found in Indonesia, Brazil, India, Russia (Siberia), and Germany.[ citation needed ]
The red variety of chalcedony has been known to be used as beads since the Early Neolithic in Bulgaria. The first faceted (with constant 16+16=32 facets on each side of the bead) carnelian beads are described from the Varna Chalcolithic necropolis (middle of the 5th millennium BC).  The bow drill was used to drill holes into carnelian in Mehrgarh in the 4th-5th millennium BC.  Carnelian was recovered from Bronze Age Minoan layers at Knossos on Crete in a form that demonstrated its use in decorative arts;  this use dates to approximately 1800 BC. Carnelian was used widely during Roman times to make engraved gems for signet or seal rings for imprinting a seal with wax on correspondence or other important documents. Hot wax does not stick to carnelian.  Sard was used for Assyrian cylinder seals, Egyptian and Phoenician scarabs, and early Greek and Etruscan gems.  The Hebrew odem (also translated as sardius), the first stone in the High Priest's breastplate, was a red stone, probably sard but perhaps red jasper.  In Revelation 4:3, the One seated on the heavenly throne seen in the vision of John the apostle is said to "look like jasper and 'σαρδίῳ' (sardius transliterated)." And likewise it is in Revelation 21:20 as one of the precious stones in the foundations of the wall of the heavenly city. 
There is a Neo-Assyrian seal made of carnelian in the Western Asiatic Seals collection of the British Museum that shows Ishtar-Gula as a star goddess. She is holding a ring of royal authority and is seated on a throne. She is shown with the spade of Marduk (his symbol), Sibbiti (seven) gods, the stylus of Nabu and a worshiper. An 8th century BC carnelian seal from the collection of the Ashmolean Museum shows Ishtar-Gula with her dog facing the spade of Marduk and his red dragon. 
Although now the more common term, "carnelian" is a 16th-century corruption of the 14th-century word "cornelian" (and its associated orthographies corneline and cornalyn).  Cornelian, cognate with similar words in several Romance languages, comes from the Mediaeval Latin corneolus, itself derived from the Latin word cornum, the cornel cherry,  whose translucent red fruits resemble the stone. The Oxford English Dictionary calls "carnelian" a perversion of "cornelian," by subsequent analogy with the Latin word caro, carnis, flesh. According to Pliny the Elder, sard derived its name from the city of Sardis in Lydia from which it came, and according to others, may ultimately be related to the Persian word سرد sered, meaning yellowish red.  Sarx in Greek means "flesh", and other stones have similar naming, such as the onyx stone in sardonyx, which came from Greek for "claw" or "fingernail" because onyx with flesh-colored and white bands can resemble a fingernail.  So this type of use analogy may have been more widespread.
The names carnelian and sard are often used interchangeably, but they can also be used to describe distinct subvarieties. The general differences are as follows: 
|Color||Lighter, with shades ranging from orange to reddish brown||Darker, with shades ranging from a deep reddish brown to almost black|
|Hardness||Softer||Harder and tougher|
|Fracture||Uneven, splintery and conchoidal||Like carnelian, but duller and more hackly (having the appearance of something that has been hacked, i.e. jagged)|
All of these properties vary across a continuum, so the boundary between carnelian and sard is inherently blurry.
Agate is a common rock formation, consisting of chalcedony and quartz as its primary components, with 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.
Jewellery or jewelry 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.
Chalcedony ( kal-SED-ə-nee, or KAL-sə-doh-nee) 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).
Lapis lazuli, or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in modern northeast Afghanistan. Lapis lazuli artifacts, dated to 7570 BC, have been found at Bhirrana, which is the oldest site of Indus Valley civilisation. Lapis was highly valued by the Indus Valley Civilisation. Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and as far away as Mauritania. It was used in the funeral mask of Tutankhamun.
Susa was an ancient city in the lower Zagros Mountains about 250 km (160 mi) east of the Tigris, between the Karkheh and Dez Rivers in Iran. One of the most important cities of the Ancient Near East, Susa served as the capital of Elam and the Achaemenid Empire, and remained a strategic centre during the Parthian and Sasanian periods.
Elam was an ancient civilization centered in the far west and southwest of modern-day Iran, stretching from the lowlands of what is now Khuzestan and Ilam Province as well as a small part of southern Iraq. The modern name Elam stems from the Sumerian transliteration elam(a), along with the later Akkadian elamtu, and the Elamite haltamti. Elamite states were among the leading political forces of the Ancient Near East. In classical literature, Elam was also known as Susiana, a name derived from its capital Susa.
Onyx primarily refers to the parallel banded variety of chalcedony, a silicate mineral. Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands: agate has curved bands and onyx has parallel bands. The colors of its bands range from black to almost every color. Commonly, specimens of onyx contain bands of black and/or white. Onyx, as a descriptive term, has also been applied to parallel banded varieties of alabaster, marble, calcite, obsidian and opal, and misleadingly to materials with contorted banding, such as "Cave Onyx" and "Mexican Onyx".
Meluḫḫa or Melukhkha is the Sumerian name of a prominent trading partner of Sumer during the Middle Bronze Age. Its identification remains an open question, but most scholars associate it with the Indus Valley civilisation.
The First Dynasty of Ur was a 26th-25th century BCE dynasty of rulers of the city of Ur in ancient Sumer. It is part of the Early Dynastic period III of the history of Mesopotamia. It was preceded by the earlier First Dynasty of Kish and the First Dynasty of Uruk.
Shulgi of Ur was the second king of the Third Dynasty of Ur. He reigned for 48 years, from c. 2094 – c. 2046 BC or possibly c. 2030 – 1982 BC. His accomplishments include the completion of construction of the Great Ziggurat of Ur, begun by his father Ur-Nammu. On his inscriptions, he took the titles "King of Ur", "King of Sumer and Akkad" and "King of the four corners of the universe". He used the symbol for divinity before his name, marking his apotheosis, from the 23rd year of his reign.
Dzi bead is a type of stone bead of uncertain origin worn as part of a necklace and sometimes as a bracelet. In several Central Asian cultures, including that of Tibet, the bead is considered to provide positive spiritual benefit. These beads are generally prized as protective amulets and are sometimes ground into a powder to be used in traditional Tibetan medicine. Beads subject to this process have small "dig marks" where a portion of the bead has been scraped or ground away to be included in the medicine. Some dzi exhibit grinding and polishing of one or both ends, again the result of reduction for use in traditional Tibetan medicine or, in some cases, due to the bead's use as a burnishing tool in the application of gold leaf to thanka paintings or gilt bronze statuary.
The Varna Necropolis, or Varna Cemetery, is a burial site in the western industrial zone of Varna, internationally considered one of the key archaeological sites in world prehistory. The oldest gold treasure and jewelry in the world, dating from 4,600 BC to 4,200 BC, was discovered at the site. Several prehistoric Bulgarian finds are considered no less old – the golden treasures of Hotnitsa, Durankulak, artifacts from the Kurgan settlement of Yunatsite near Pazardzhik, the golden treasure Sakar, as well as beads and gold jewelry found in the Kurgan settlement of Provadia – Solnitsata. However, Varna gold is most often called the oldest since this treasure is the largest and most diverse.
Dholavira is an archaeological site at Khadirbet in Bhachau Taluka of Kutch District, in the state of Gujarat in western India, which has taken its name from a modern-day village 1 kilometre (0.62 mi) south of it. This village is 165 km (103 mi) from Radhanpur. Also known locally as Kotada timba, the site contains ruins of a city of the ancient Indus Valley civilization. Earthquakes have repeatedly affected Dholavira, including a particularly severe one around 2600 BC.
Aqeeq, akik or aqiq means quartz in Arabic, and agate in Turkish, however in the context of rings usually refers to a ring set with a chalcedony stone. Well-known types of chalcedony are carnelian, agate, and onyx. It is considered a semi-precious gem stone, and rings set with golden-orange variety of carnelian or sard have special significance in the Islamic religion.
A range of gemstones are mentioned in the Bible, particularly in the Old Testament and the Book of Revelation. Much has been written about the precise identification of these stones, although largely speculative.
Hardstone carving is a general term in art history and archaeology for the artistic carving of predominantly semi-precious stones, such as jade, rock crystal, agate, onyx, jasper, serpentinite, or carnelian, and for an object 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 is the common term used for stone inlay work, which causes some confusion.
Imports to Ur reflect the cultural and trade connections of the Sumerian city of Ur. During the period of the Early Dynastic III royal cemetery, Ur was importing elite goods from geographically distant places. These objects include precious metals such as gold and silver, and semi-precious stones, namely lapis lazuli and carnelian. These objects are all the more impressive considering the distance from which they traveled to reach Mesopotamia and Ur specifically.
Indus–Mesopotamia relations are thought to have developed during the second half of 3rd millennium BCE, until they came to a halt with the extinction of the Indus valley civilization after around 1900 BCE. Mesopotamia had already been an intermediary in the trade of lapis lazuli between the Indian subcontinent and Egypt since at least about 3200 BCE, in the context of Egypt-Mesopotamia relations.
Etched carnelian beads, or sometimes bleached carnelian beads, are a type of ancient decorative beads made from carnelian with an etched design in white, which were probably manufactured by the Indus Valley civilization during the 3rd millennium BCE. They were made according to a technique of alkaline-etching developed by the Harappans, and vast quantities of these beads were found in the archaeological sites of the Indus Valley civilization. They are considered as an important marker of ancient trade between the Indus Valley, Mesopotamia and even Ancient Egypt, as these precious and unique manufactured items circulated in great numbers between these geographical areas during the 3rd millennium BCE, and have been found in numerous tomb deposits.
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