Emerald in the context of Hardness

A ring is a round band, usually made of metal, worn as ornamental jewelry. The term "ring" by itself denotes jewellery worn on the finger; when worn as an ornament elsewhere, the body part is specified within the term, e.g., earrings, neck rings, arm rings, and toe rings. Rings fit snugly around or in the part of the body they ornament, so bands worn loosely, like a bracelet, are not rings. Rings may be made of almost any hard material: wood, bone, stone, metal, glass, jade, gemstone or plastic. They may be set with gemstones (diamond, ruby, sapphire or emerald) or with other types of stone or glass.

Although some people wear rings as mere ornaments or as conspicuous displays of wealth, rings have symbolic functions respecting marriage, exceptional achievement, high status or authority, membership in an organization, and the like. Rings can be made to sport insignia which may be impressed on a wax seal or outfitted with a small compartment in which to conceal things.

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.

A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments. Certain rocks (such as lapis lazuli, opal, and obsidian) and occasionally organic materials that are not minerals (such as amber, jet, and pearl) may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value. However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability.

Found all over the world, the industry of coloured gemstones (i.e. anything other than diamonds) is currently estimated at US$1.55 billion as of 2023 and is projected to steadily increase to a value of $4.46 billion by 2033.

Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495–570 nm. In subtractive color systems, used in painting and color printing, it is created by a combination of yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content.

During post-classical and early modern Europe, green was the color commonly associated with wealth, merchants, bankers, and the gentry, while red was reserved for the nobility. For this reason, the costume of the Mona Lisa by Leonardo da Vinci and the benches in the British House of Commons are green while those in the House of Lords are red. It also has a long historical tradition as the color of Ireland and of Gaelic culture. It is the historic color of Islam, representing the lush vegetation of Paradise. It was the color of the banner of Muhammad, and is found in the flags of nearly all Islamic countries.

Ruby is a pinkish-red to blood-red gemstone, a variety of the mineral corundum (aluminium oxide). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires; given that the rest of the corundum species are called as such, rubies are sometimes referred to as "red sapphires".

Ruby is one of the traditional cardinal gems, alongside amethyst, sapphire, emerald, and diamond. The word ruby comes from ruber, Latin for red. The color of a ruby is due to the presence of chromium.

The papal tiara is a crown that was worn by popes of the Catholic Church from as early as the 8th century to the mid–20th century. It was last used by Pope Paul VI in 1963, and only at the beginning of his reign.

The name tiara refers to the entire headpiece, including the various crowns, circlets, and diadems that have adorned it through the ages, while the three-tiered form that it took in the 14th century is also called the triregnum or the triple crown, and sometimes as the triple tiara.

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.

From the Neolithic period until about the 19th century such objects were among the most highly prized in a wide variety of cultures, often attributed special powers or religious significance, but today coverage in non-specialist art history tends to be relegated to a catch-all decorative arts or "minor arts" category. The types of objects carved have included those with ritual or religious purposes, engraved gems as signet rings and other kinds of seal, handles, belt hooks and similar items, vessels and purely decorative objects.

The Spanish conquest of the Muisca took place from 1537 to 1540. The Muisca were the inhabitants of the central Andean highlands of Colombia before the arrival of the Spanish conquistadors. They were organised in a loose confederation of different rulers; the psihipqua of Muyquytá, with his headquarters in Funza, the hoa of Hunza, the iraca of the sacred City of the Sun Sugamuxi, the Tundama of Tundama, and several other independent caciques. The most important rulers at the time of the conquest were psihipqua Tisquesusa, hoa Eucaneme, iraca Sugamuxi and Tundama in the northernmost portion of their territories. The Muisca were organised in small communities of circular enclosures (ca in their language Muysccubbun; literally "language of the people"), with a central square where the bohío of the cacique was located. They were called "Salt People" because of their extraction of salt in various locations throughout their territories, mainly in Zipaquirá, Nemocón, and Tausa. For the main part self-sufficient in their well-organised economy, the Muisca traded with the European conquistadors valuable products as gold, tumbaga (a copper-silver-gold alloy), and emeralds with their neighbouring indigenous groups. In the Tenza Valley, to the east of the Altiplano Cundiboyacense where the majority of the Muisca lived, they extracted emeralds in Chivor and Somondoco. The economy of the Muisca was rooted in their agriculture with main products maize, yuca, potatoes, and various other cultivations elaborated on elevated fields (in their language called tá). Agriculture had started around 3000 BCE on the Altiplano, following the preceramic Herrera Period and a long epoch of hunter-gatherers since the late Pleistocene. The earliest archaeological evidence of inhabitation in Colombia, and one of the oldest in South America, has been found in El Abra, dating to around 12,500 years BP.

The main part of the Muisca civilisation was concentrated on the Bogotá savanna, a flat high plain in the Eastern Ranges of the Andes, far away from the Caribbean coast. The savanna was an ancient lake, that existed until the latest Pleistocene and formed a highly fertile soil for their agriculture. The Muisca were a deeply religious civilisation with a polytheistic society and an advanced astronomical knowledge, which was represented in their complex lunisolar calendar. Men and women had specific and different tasks in their relatively egalitarian society; while the women took care of the sowing, preparation of food, the extraction of salt, and the elaboration of mantles and pottery, the men were assigned to harvesting, warfare, and hunting. The guecha warriors were tasked with the defence of the Muisca territories, mainly against their western neighbours; the Muzo ("Emerald People") and the bellicose Panche. To impress their enemies, the Muisca warriors wore mummies of important ancestors on their backs, while fighting. In their battles, the men used spears, poisoned arrows, and golden knives.

Beryllium is a chemical element; it has symbol Be and atomic number 4. It is a steel-gray, hard, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form minerals. Gemstones high in beryllium include beryl (aquamarine, emerald, red beryl) and chrysoberyl. It is a relatively rare element in the universe, usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Within the cores of stars, beryllium is depleted as it is fused into heavier elements. Beryllium constitutes about 0.0004 percent by mass of Earth's crust. The world's annual beryllium production of 220 tons is usually manufactured by extraction from the mineral beryl, a difficult process because beryllium bonds strongly to oxygen.

In structural applications, the combination of high flexural rigidity, thermal stability, thermal conductivity and low density (1.85 times that of water) make beryllium a desirable aerospace material for aircraft components, missiles, spacecraft, and satellites. Because of its low density and atomic mass, beryllium is relatively transparent to X-rays and other forms of ionizing radiation; therefore, it is the most common window material for X-ray equipment and components of particle detectors. When added as an alloying element to aluminium, copper (notably the alloy beryllium copper), iron, or nickel, beryllium improves many physical properties. For example, tools and components made of beryllium copper alloys are strong and hard and do not create sparks when they strike a steel surface. In air, the surface of beryllium oxidizes readily at room temperature to form a passivation layer 1–10 nm thick that protects it from further oxidation and corrosion. The metal oxidizes in bulk (beyond the passivation layer) when heated above 500 °C (932 °F), and burns brilliantly when heated to about 2,500 °C (4,530 °F).

Cardinal gems are gemstones which have traditionally been considered precious above all others. The classification of the cardinal gems dates back to antiquity, and was largely determined by ceremonial or religious use as well as rarity. The term has largely fallen out of use.

Beryl (/ˈbɛrəl/ BERR-əl) is a mineral composed of beryllium aluminium silicate with the chemical formula Be₃Al₂(SiO₃)₆. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring hexagonal crystals of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of beryllium.

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.

An unguentarium (pl.: unguentaria), also referred to as balsamarium (pl.: balsamaria), lacrimarium (pl.: lacrimaria) or tears vessel, is a small ceramic or glass bottle found frequently by archaeologists at Hellenistic and Roman sites, especially in cemeteries. Its most common use was probably as a container for oil, though it is also suited for storing and dispensing liquid and powdered substances. Some finds date into the early Christian era. From the 2nd to the 6th century they are more often made of blown glass rather than clay. A few examples are silver or alabaster.

Unguentaria were used as product packaging in commerce and for funerary practice. They are distributed throughout the Mediterranean region of the Roman Empire from Israel to Spain, and north into Britain and Germania. Their manufacture was nearly as widespread.