Sapphire in the context of "Tourmaline"

Emery, or corundite, is a dark granular rock used to make an abrasive powder. The rock largely consists of corundum (aluminium oxide), mixed with other minerals. Industrial emery may contain a variety of other minerals and synthetic compounds. Crushed or naturally eroded emery (known as black sand) is used as an abrasive. Turkey and Greece are the main suppliers of the world's emery.

Corundum is a crystalline form of aluminium oxide (Al₂O₃) typically containing traces of iron, titanium, vanadium, and chromium. It is a rock-forming mineral. It is a naturally transparent material, but can have different colors depending on the presence of transition metal impurities in its crystalline structure. Corundum has two primary gem varieties: ruby and sapphire. Rubies are red due to the presence of chromium, and sapphires exhibit a range of colors depending on what transition metal is present. A rare type of sapphire, padparadscha sapphire, is pink-orange.

The name "corundum" is derived from the Tamil-Dravidian word kurundam (ruby-sapphire) (appearing in Sanskrit as kuruvinda).

The Treasure of Guarrazar, Guadamur, Province of Toledo, Castile-La Mancha, Spain, is an archeological find composed of twenty-six votive crowns and gold crosses that had originally been offered to the Catholic Church by the Kings Visigoths in the seventh century in Hispania, as a gesture of the orthodoxy of their faith and their submission to the ecclesiastical hierarchy. The most valuable of all is the votive crown of king Recceswinth with its blue sapphires from Sri Lanka and pendilia. Though the treasure is now divided and much has disappeared, it represents the best surviving group of Early Medieval Christian votive offerings.

The treasure, which represents the high point of Visigothic gold craftsmanship, was dug between 1858 and 1861 in an orchard called Guarrazar, in Guadamur, very close to Toledo, Spain. The treasure was divided, with some objects going to the Musée de Cluny in Paris and the rest to the armouries of the Palacio Real in Madrid (today in the National Archaeological Museum of Spain). In 1921 and 1936, some items of the Treasure of Guarrazar were stolen and have disappeared.

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.

Aluminium oxide (or aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula Al₂O₃. It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, ALOX or alundum in various forms and applications and alumina is refined from bauxite. It occurs naturally in its crystalline polymorphic phase α-Al₂O₃ as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire, which have an alumina content approaching 100%. Al₂O₃ is used as feedstock to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point.

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.