An amulet is an object that is typically worn on one's person, that some people believe has the magical or miraculous power to protect its holder, either to protect them in general or to protect them from some specific thing; it is often also used as an ornament though that may not be the intended purpose of it.  Amulets which are said to derive their extraordinary properties and powers from magic or those which impart luck are typically part of folk religion or paganism, whereas amulets or sacred objects of formalised mainstream religion as in Christianity are believed to have no power of their own without being blessed by a clergyman, and they supposedly will also not provide any preternatural benefit to the bearer who does not have an appropriate disposition. Amulets are different from talismans and charms because they may have alleged magical powers other than protection. Amulets are sometimes confused with pendants, small aesthetic objects that hang from necklaces. Any given pendant may indeed be an amulet but so may any other object that purportedly protects its holder from danger.
Potential amulets include gems, especially engraved gems, statues, coins, drawings, pendants, rings, plant parts, animal parts, and even written words in the form of a magical spell or incantation to repel evil or bad luck. Magic scrolls are found to be used in various cultures, and artifacts of scrolls with magical inscriptions have been found in the Middle East, Europe, and the Far East.
The word "amulet" comes from the Latin word amulētum. The earliest extant use of that term is in Pliny the Elder's Natural History in which it means "an object that protects a person from trouble".
Amulets were particularly prevalent in ancient Roman society, being the inheritor of the ancient Greek tradition, and inextricably linked to Roman religion and magic (see magic in the Graeco-Roman world). Amulets are usually outside of the normal sphere of religious experience, though associations between certain gemstones and gods has been suggested. For example, Jupiter is represented on milky chalcedony, Sol on heliotrope, Mars on red jasper, Ceres on green jasper, and Bacchus on amethyst. Amulets are worn to imbue the wearer with the associated powers of the gods rather than for any reasons of piety. The intrinsic power of the amulet is also evident from others bearing inscriptions, such as vterfexix (utere fexix) or "good luck to the user." Amulet boxes could also be used, such as the example from part of the Thetford treasure, Norfolk, UK, where a gold box intended for suspension around the neck was found to contain sulphur for its apotropaic (evil-repelling) qualities.
In antiquity and the Middle Ages, most Jews, Christians, and Muslims in the Orient believed in the protective and healing power of amulets or blessed objects. Talismans used by these peoples can be broken down into three main categories: talismans carried or worn on the body, talismans hung upon or above the bed of an infirm person, and medicinal talismans. This third category can be further divided into external and internal talismans. For example, an external amulet can be placed in a bath.
Jews, Christians, and Muslims have also at times used their holy books in a talisman-like manner in grave situations. For example, a bed-ridden and seriously ill person would have a holy book placed under part of the bed or cushion.
Amulets are plentiful in the Jewish tradition, with examples of Solomon-era amulets existing in many museums. Due to the proscription of idols and other graven images in Judaism, Jewish amulets emphasize text and names. The shape, material, and color of a Jewish amulet makes no difference. Examples of textual amulets include the Silver Scroll, circa 630 BCE, and the still contemporary mezuzah and tefillin. A counter-example, however, is the Hand of Miriam, an outline of a human hand. Another non-textual amulet is the Seal of Solomon, also known as the hexagram or Star of David. In one form. it consists of two intertwined equilateral triangles, and in this form it is commonly worn suspended around the neck to this day.
Another common amulet in contemporary use is the Chai (symbol)—(Hebrew: חַי "living" ḥay), which is also worn around the neck. Other similar amulets still in use consist of one of the names of the god of Judaism, such as ה (He), יה (YaH), or שדי (Shaddai), inscribed on a piece of parchment or metal, usually silver.
During the Middle Ages, Maimonides and Sherira Gaon (and his son Hai Gaon) opposed the use of amulets and derided the "folly of amulet writers." Other rabbis, however, approved the use of amulets.
Rabbi and famous kabbalist Naphtali ben Isaac Katz ("Ha-Kohen," 1645–1719) was said to be an expert in the magical use of amulets. He was accused of causing a fire that broke out in his house and then destroyed the whole Jewish quarter of Frankfurt, and of preventing the extinguishing of the fire by conventional means because he wanted to test the power of his amulets; he was imprisoned and forced to resign his post and leave the city.
The Roman Catholic Church maintains that the legitimate use of sacramentals in its proper disposition is encouraged only by a firm faith and devotion to the Triune God, and not by any magical or superstitious belief bestowed on the sacramental. In this regard, rosaries, scapulars, medals, and other devotional religious Catholic paraphernalia derive their power, not simply from the symbolism displayed in the object, but rather from the blessing of the Catholic Church which comes from God.
Lay Catholics are not permitted to perform solemn exorcisms, but they can use holy water, blessed salt, and other sacramentals, such as the Saint Benedict medal or the crucifix, for warding off evil.
The crucifix, and the associated sign of the cross, is one of the key sacramentals used by Catholics to ward off evil since the time of the Early Church Fathers. The imperial cross of Conrad II (1024–1039) referred to the power of the cross against evil.
A well-known amulet among Catholic Christians is the Saint Benedict medal which includes the Vade Retro Satana formula to ward off Satan. This medal has been in use at least since the 1700s, and in 1742 it received the approval of Pope Benedict XIV. It later became part of the Roman Catholic ritual.
Some Catholic sacramentals are believed to defend against evil, by virtue of their association with a specific saint or archangel. The scapular of St. Michael the Archangel is a Roman Catholic devotional scapular associated with Archangel Michael, the chief enemy of Satan. Pope Pius IX gave this scapular his blessing, but it was first formally approved under Pope Leo XIII.
The form of this scapular is somewhat distinct, in that the two segments of cloth that constitute it have the form of a small shield; one is made of blue and the other of black cloth, and one of the bands likewise is blue and the other black. Both portions of the scapular bear the well-known representation of the Archangel St. Michael slaying the dragon and the inscription "Quis ut Deus?" meaning "Who is like God?".
Catholic saints have written about the power of holy water as a force that repels evil. Saint Teresa of Avila, a Doctor of the Church who reported visions of Jesus and Mary, was a strong believer in the power of holy water and wrote that she used it with success to repel evil and temptations.
In Central and West Asia, amulets (often in the form of triangular packages containing a sacred verse) were traditionally attached to the clothing of babies and young children to give them protection from forces such as the evil eye. Triangular amulet motifs were often also woven into oriental carpets such as kilims. The carpet expert Jon Thompson explains that such an amulet woven into a rug is not a theme: it actually is an amulet, conferring protection by its presence. In his words, "the device in the rug has a materiality, it generates a field of force able to interact with other unseen forces and is not merely an intellectual abstraction."
The Tibetan Buddhists have many kinds of talismanic and shamanistic amulets and ritual tools, including the dorje, the bell, and many kinds of portable amulets. The Tibetan Buddhists enclose prayers on a parchment scroll within a prayer wheel, which is then spun around, each rotation being one recitation of all of the stanzas within the prayer wheel.
The people of Thailand, with Buddhist and animist beliefs, also have a vast pantheon of amulets, which are still popular and in common use by most people even in the present day. The belief in magic is impregnated into Thai culture and religious beliefs and folk superstitions, and this is reflected in the fact that we can still see commonplace use of amulets and magical rituals in everyday life. Some of the more commonly known amulets are of course the Buddhist votive tablets, such as the Pra Somdej Buddha image, and guru monk coins. But Thailand has an immensely large number of magical traditions, and thousands of different types of amulet and occult charm can be found in use, ranging from the takrut scroll spell, to the necromantic Ban Neng Chin Aathan, which uses the bones or flesh of the corpse of a 'hoeng prai' ghost (a person who died unnaturally, screaming, or in other strange premature circumstances), to reanimate the spirit of the dead, to dwell within the bone as a spirit, and assist the owner to achieve their goals. The list of Thai Buddhist amulets in existence is a lifetime study in its own right, and indeed, many people devote their lives to the study of them, and collection. Thai amulets are still immensely popular both with Thai folk as well as with foreigners, and in recent years, a massive increase in foreign interest has caused the subject of Thai Buddhist amulets to become a commonly known topic around the world. Amulets can fetch prices ranging from a few dollars right up to millions of dollars for a single amulet. Due to the money that can be made with sorcery services, and with rare collector amulets of the master class, there is also a forgery market in existence, which ensures that the experts of the scene maintain a monopoly on the market. With so many fakes, experts are needed for collectors to trust for obtaining authentic amulets, and not selling them fakes.
Amulets vary considerably according to their time and place of origin. In many societies, religious objects serve as amulets, e.g. deriving from the ancient Celts, the clover, if it has four leaves, symbolizes good luck (not the Irish shamrock, which symbolizes the Christian Trinity).
In certain areas of India, Nepal and Sri Lanka, it is traditionally believed that the jackal's horn can grant wishes and reappear to its owner at its own accord when lost. Some Sinhalese believe that the horn can grant the holder invulnerability in any lawsuit.
In the Philippines, amulets are called agimat or anting-anting. According to folklore, the most powerful anting-anting is the hiyas ng saging (directly translated as pearl or gem of the banana). The hiyas must come from a mature banana and only comes out during midnight. Before the person can fully possess this agimat, he must fight a supernatural creature called kapre. Only then will he be its true owner. During Holy Week, devotees travel to Mount Banahaw to recharge their amulets.